1 /* 2 * ng_base.c 3 */ 4 5 /*- 6 * Copyright (c) 1996-1999 Whistle Communications, Inc. 7 * All rights reserved. 8 * 9 * Subject to the following obligations and disclaimer of warranty, use and 10 * redistribution of this software, in source or object code forms, with or 11 * without modifications are expressly permitted by Whistle Communications; 12 * provided, however, that: 13 * 1. Any and all reproductions of the source or object code must include the 14 * copyright notice above and the following disclaimer of warranties; and 15 * 2. No rights are granted, in any manner or form, to use Whistle 16 * Communications, Inc. trademarks, including the mark "WHISTLE 17 * COMMUNICATIONS" on advertising, endorsements, or otherwise except as 18 * such appears in the above copyright notice or in the software. 19 * 20 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND 21 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO 22 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE, 23 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF 24 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. 25 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY 26 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS 27 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE. 28 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES 29 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING 30 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 31 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR 32 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY 33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 35 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY 36 * OF SUCH DAMAGE. 37 * 38 * Authors: Julian Elischer <julian@freebsd.org> 39 * Archie Cobbs <archie@freebsd.org> 40 * 41 * $FreeBSD$ 42 * $Whistle: ng_base.c,v 1.39 1999/01/28 23:54:53 julian Exp $ 43 */ 44 45 /* 46 * This file implements the base netgraph code. 47 */ 48 49 #include <sys/param.h> 50 #include <sys/systm.h> 51 #include <sys/ctype.h> 52 #include <sys/errno.h> 53 #include <sys/kdb.h> 54 #include <sys/kernel.h> 55 #include <sys/ktr.h> 56 #include <sys/limits.h> 57 #include <sys/malloc.h> 58 #include <sys/mbuf.h> 59 #include <sys/queue.h> 60 #include <sys/sysctl.h> 61 #include <sys/syslog.h> 62 #include <sys/refcount.h> 63 #include <sys/proc.h> 64 65 #include <net/netisr.h> 66 67 #include <netgraph/ng_message.h> 68 #include <netgraph/netgraph.h> 69 #include <netgraph/ng_parse.h> 70 71 MODULE_VERSION(netgraph, NG_ABI_VERSION); 72 73 /* Mutex to protect topology events. */ 74 static struct mtx ng_topo_mtx; 75 76 #ifdef NETGRAPH_DEBUG 77 static struct mtx ng_nodelist_mtx; /* protects global node/hook lists */ 78 static struct mtx ngq_mtx; /* protects the queue item list */ 79 80 static SLIST_HEAD(, ng_node) ng_allnodes; 81 static LIST_HEAD(, ng_node) ng_freenodes; /* in debug, we never free() them */ 82 static SLIST_HEAD(, ng_hook) ng_allhooks; 83 static LIST_HEAD(, ng_hook) ng_freehooks; /* in debug, we never free() them */ 84 85 static void ng_dumpitems(void); 86 static void ng_dumpnodes(void); 87 static void ng_dumphooks(void); 88 89 #endif /* NETGRAPH_DEBUG */ 90 /* 91 * DEAD versions of the structures. 92 * In order to avoid races, it is sometimes neccesary to point 93 * at SOMETHING even though theoretically, the current entity is 94 * INVALID. Use these to avoid these races. 95 */ 96 struct ng_type ng_deadtype = { 97 NG_ABI_VERSION, 98 "dead", 99 NULL, /* modevent */ 100 NULL, /* constructor */ 101 NULL, /* rcvmsg */ 102 NULL, /* shutdown */ 103 NULL, /* newhook */ 104 NULL, /* findhook */ 105 NULL, /* connect */ 106 NULL, /* rcvdata */ 107 NULL, /* disconnect */ 108 NULL, /* cmdlist */ 109 }; 110 111 struct ng_node ng_deadnode = { 112 "dead", 113 &ng_deadtype, 114 NGF_INVALID, 115 1, /* refs */ 116 0, /* numhooks */ 117 NULL, /* private */ 118 0, /* ID */ 119 LIST_HEAD_INITIALIZER(ng_deadnode.hooks), 120 {}, /* all_nodes list entry */ 121 {}, /* id hashtable list entry */ 122 {}, /* workqueue entry */ 123 { 0, 124 {}, /* should never use! (should hang) */ 125 NULL, 126 &ng_deadnode.nd_input_queue.queue, 127 &ng_deadnode 128 }, 129 #ifdef NETGRAPH_DEBUG 130 ND_MAGIC, 131 __FILE__, 132 __LINE__, 133 {NULL} 134 #endif /* NETGRAPH_DEBUG */ 135 }; 136 137 struct ng_hook ng_deadhook = { 138 "dead", 139 NULL, /* private */ 140 HK_INVALID | HK_DEAD, 141 1, /* refs always >= 1 */ 142 0, /* undefined data link type */ 143 &ng_deadhook, /* Peer is self */ 144 &ng_deadnode, /* attached to deadnode */ 145 {}, /* hooks list */ 146 NULL, /* override rcvmsg() */ 147 NULL, /* override rcvdata() */ 148 #ifdef NETGRAPH_DEBUG 149 HK_MAGIC, 150 __FILE__, 151 __LINE__, 152 {NULL} 153 #endif /* NETGRAPH_DEBUG */ 154 }; 155 156 /* 157 * END DEAD STRUCTURES 158 */ 159 /* List nodes with unallocated work */ 160 static TAILQ_HEAD(, ng_node) ng_worklist = TAILQ_HEAD_INITIALIZER(ng_worklist); 161 static struct mtx ng_worklist_mtx; /* MUST LOCK NODE FIRST */ 162 163 /* List of installed types */ 164 static LIST_HEAD(, ng_type) ng_typelist; 165 static struct mtx ng_typelist_mtx; 166 167 /* Hash related definitions */ 168 /* XXX Don't need to initialise them because it's a LIST */ 169 #define NG_ID_HASH_SIZE 128 /* most systems wont need even this many */ 170 static LIST_HEAD(, ng_node) ng_ID_hash[NG_ID_HASH_SIZE]; 171 static struct mtx ng_idhash_mtx; 172 /* Method to find a node.. used twice so do it here */ 173 #define NG_IDHASH_FN(ID) ((ID) % (NG_ID_HASH_SIZE)) 174 #define NG_IDHASH_FIND(ID, node) \ 175 do { \ 176 mtx_assert(&ng_idhash_mtx, MA_OWNED); \ 177 LIST_FOREACH(node, &ng_ID_hash[NG_IDHASH_FN(ID)], \ 178 nd_idnodes) { \ 179 if (NG_NODE_IS_VALID(node) \ 180 && (NG_NODE_ID(node) == ID)) { \ 181 break; \ 182 } \ 183 } \ 184 } while (0) 185 186 #define NG_NAME_HASH_SIZE 128 /* most systems wont need even this many */ 187 static LIST_HEAD(, ng_node) ng_name_hash[NG_NAME_HASH_SIZE]; 188 static struct mtx ng_namehash_mtx; 189 #define NG_NAMEHASH(NAME, HASH) \ 190 do { \ 191 u_char h = 0; \ 192 const u_char *c; \ 193 for (c = (const u_char*)(NAME); *c; c++)\ 194 h += *c; \ 195 (HASH) = h % (NG_NAME_HASH_SIZE); \ 196 } while (0) 197 198 199 /* Internal functions */ 200 static int ng_add_hook(node_p node, const char *name, hook_p * hookp); 201 static int ng_generic_msg(node_p here, item_p item, hook_p lasthook); 202 static ng_ID_t ng_decodeidname(const char *name); 203 static int ngb_mod_event(module_t mod, int event, void *data); 204 static void ng_worklist_remove(node_p node); 205 static void ngintr(void); 206 static int ng_apply_item(node_p node, item_p item, int rw); 207 static void ng_flush_input_queue(struct ng_queue * ngq); 208 static void ng_setisr(node_p node); 209 static node_p ng_ID2noderef(ng_ID_t ID); 210 static int ng_con_nodes(item_p item, node_p node, const char *name, 211 node_p node2, const char *name2); 212 static int ng_con_part2(node_p node, item_p item, hook_p hook); 213 static int ng_con_part3(node_p node, item_p item, hook_p hook); 214 static int ng_mkpeer(node_p node, const char *name, 215 const char *name2, char *type); 216 217 /* Imported, these used to be externally visible, some may go back. */ 218 void ng_destroy_hook(hook_p hook); 219 node_p ng_name2noderef(node_p node, const char *name); 220 int ng_path2noderef(node_p here, const char *path, 221 node_p *dest, hook_p *lasthook); 222 int ng_make_node(const char *type, node_p *nodepp); 223 int ng_path_parse(char *addr, char **node, char **path, char **hook); 224 void ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3); 225 void ng_unname(node_p node); 226 227 228 /* Our own netgraph malloc type */ 229 MALLOC_DEFINE(M_NETGRAPH, "netgraph", "netgraph structures and ctrl messages"); 230 MALLOC_DEFINE(M_NETGRAPH_HOOK, "netgraph_hook", "netgraph hook structures"); 231 MALLOC_DEFINE(M_NETGRAPH_NODE, "netgraph_node", "netgraph node structures"); 232 MALLOC_DEFINE(M_NETGRAPH_ITEM, "netgraph_item", "netgraph item structures"); 233 MALLOC_DEFINE(M_NETGRAPH_MSG, "netgraph_msg", "netgraph name storage"); 234 235 /* Should not be visible outside this file */ 236 237 #define _NG_ALLOC_HOOK(hook) \ 238 MALLOC(hook, hook_p, sizeof(*hook), M_NETGRAPH_HOOK, M_NOWAIT | M_ZERO) 239 #define _NG_ALLOC_NODE(node) \ 240 MALLOC(node, node_p, sizeof(*node), M_NETGRAPH_NODE, M_NOWAIT | M_ZERO) 241 242 #define NG_QUEUE_LOCK_INIT(n) \ 243 mtx_init(&(n)->q_mtx, "ng_node", NULL, MTX_DEF) 244 #define NG_QUEUE_LOCK(n) \ 245 mtx_lock(&(n)->q_mtx) 246 #define NG_QUEUE_UNLOCK(n) \ 247 mtx_unlock(&(n)->q_mtx) 248 #define NG_WORKLIST_LOCK_INIT() \ 249 mtx_init(&ng_worklist_mtx, "ng_worklist", NULL, MTX_DEF) 250 #define NG_WORKLIST_LOCK() \ 251 mtx_lock(&ng_worklist_mtx) 252 #define NG_WORKLIST_UNLOCK() \ 253 mtx_unlock(&ng_worklist_mtx) 254 255 #ifdef NETGRAPH_DEBUG /*----------------------------------------------*/ 256 /* 257 * In debug mode: 258 * In an attempt to help track reference count screwups 259 * we do not free objects back to the malloc system, but keep them 260 * in a local cache where we can examine them and keep information safely 261 * after they have been freed. 262 * We use this scheme for nodes and hooks, and to some extent for items. 263 */ 264 static __inline hook_p 265 ng_alloc_hook(void) 266 { 267 hook_p hook; 268 SLIST_ENTRY(ng_hook) temp; 269 mtx_lock(&ng_nodelist_mtx); 270 hook = LIST_FIRST(&ng_freehooks); 271 if (hook) { 272 LIST_REMOVE(hook, hk_hooks); 273 bcopy(&hook->hk_all, &temp, sizeof(temp)); 274 bzero(hook, sizeof(struct ng_hook)); 275 bcopy(&temp, &hook->hk_all, sizeof(temp)); 276 mtx_unlock(&ng_nodelist_mtx); 277 hook->hk_magic = HK_MAGIC; 278 } else { 279 mtx_unlock(&ng_nodelist_mtx); 280 _NG_ALLOC_HOOK(hook); 281 if (hook) { 282 hook->hk_magic = HK_MAGIC; 283 mtx_lock(&ng_nodelist_mtx); 284 SLIST_INSERT_HEAD(&ng_allhooks, hook, hk_all); 285 mtx_unlock(&ng_nodelist_mtx); 286 } 287 } 288 return (hook); 289 } 290 291 static __inline node_p 292 ng_alloc_node(void) 293 { 294 node_p node; 295 SLIST_ENTRY(ng_node) temp; 296 mtx_lock(&ng_nodelist_mtx); 297 node = LIST_FIRST(&ng_freenodes); 298 if (node) { 299 LIST_REMOVE(node, nd_nodes); 300 bcopy(&node->nd_all, &temp, sizeof(temp)); 301 bzero(node, sizeof(struct ng_node)); 302 bcopy(&temp, &node->nd_all, sizeof(temp)); 303 mtx_unlock(&ng_nodelist_mtx); 304 node->nd_magic = ND_MAGIC; 305 } else { 306 mtx_unlock(&ng_nodelist_mtx); 307 _NG_ALLOC_NODE(node); 308 if (node) { 309 node->nd_magic = ND_MAGIC; 310 mtx_lock(&ng_nodelist_mtx); 311 SLIST_INSERT_HEAD(&ng_allnodes, node, nd_all); 312 mtx_unlock(&ng_nodelist_mtx); 313 } 314 } 315 return (node); 316 } 317 318 #define NG_ALLOC_HOOK(hook) do { (hook) = ng_alloc_hook(); } while (0) 319 #define NG_ALLOC_NODE(node) do { (node) = ng_alloc_node(); } while (0) 320 321 322 #define NG_FREE_HOOK(hook) \ 323 do { \ 324 mtx_lock(&ng_nodelist_mtx); \ 325 LIST_INSERT_HEAD(&ng_freehooks, hook, hk_hooks); \ 326 hook->hk_magic = 0; \ 327 mtx_unlock(&ng_nodelist_mtx); \ 328 } while (0) 329 330 #define NG_FREE_NODE(node) \ 331 do { \ 332 mtx_lock(&ng_nodelist_mtx); \ 333 LIST_INSERT_HEAD(&ng_freenodes, node, nd_nodes); \ 334 node->nd_magic = 0; \ 335 mtx_unlock(&ng_nodelist_mtx); \ 336 } while (0) 337 338 #else /* NETGRAPH_DEBUG */ /*----------------------------------------------*/ 339 340 #define NG_ALLOC_HOOK(hook) _NG_ALLOC_HOOK(hook) 341 #define NG_ALLOC_NODE(node) _NG_ALLOC_NODE(node) 342 343 #define NG_FREE_HOOK(hook) do { FREE((hook), M_NETGRAPH_HOOK); } while (0) 344 #define NG_FREE_NODE(node) do { FREE((node), M_NETGRAPH_NODE); } while (0) 345 346 #endif /* NETGRAPH_DEBUG */ /*----------------------------------------------*/ 347 348 /* Set this to kdb_enter("X") to catch all errors as they occur */ 349 #ifndef TRAP_ERROR 350 #define TRAP_ERROR() 351 #endif 352 353 static ng_ID_t nextID = 1; 354 355 #ifdef INVARIANTS 356 #define CHECK_DATA_MBUF(m) do { \ 357 struct mbuf *n; \ 358 int total; \ 359 \ 360 M_ASSERTPKTHDR(m); \ 361 for (total = 0, n = (m); n != NULL; n = n->m_next) { \ 362 total += n->m_len; \ 363 if (n->m_nextpkt != NULL) \ 364 panic("%s: m_nextpkt", __func__); \ 365 } \ 366 \ 367 if ((m)->m_pkthdr.len != total) { \ 368 panic("%s: %d != %d", \ 369 __func__, (m)->m_pkthdr.len, total); \ 370 } \ 371 } while (0) 372 #else 373 #define CHECK_DATA_MBUF(m) 374 #endif 375 376 #define ERROUT(x) do { error = (x); goto done; } while (0) 377 378 /************************************************************************ 379 Parse type definitions for generic messages 380 ************************************************************************/ 381 382 /* Handy structure parse type defining macro */ 383 #define DEFINE_PARSE_STRUCT_TYPE(lo, up, args) \ 384 static const struct ng_parse_struct_field \ 385 ng_ ## lo ## _type_fields[] = NG_GENERIC_ ## up ## _INFO args; \ 386 static const struct ng_parse_type ng_generic_ ## lo ## _type = { \ 387 &ng_parse_struct_type, \ 388 &ng_ ## lo ## _type_fields \ 389 } 390 391 DEFINE_PARSE_STRUCT_TYPE(mkpeer, MKPEER, ()); 392 DEFINE_PARSE_STRUCT_TYPE(connect, CONNECT, ()); 393 DEFINE_PARSE_STRUCT_TYPE(name, NAME, ()); 394 DEFINE_PARSE_STRUCT_TYPE(rmhook, RMHOOK, ()); 395 DEFINE_PARSE_STRUCT_TYPE(nodeinfo, NODEINFO, ()); 396 DEFINE_PARSE_STRUCT_TYPE(typeinfo, TYPEINFO, ()); 397 DEFINE_PARSE_STRUCT_TYPE(linkinfo, LINKINFO, (&ng_generic_nodeinfo_type)); 398 399 /* Get length of an array when the length is stored as a 32 bit 400 value immediately preceding the array -- as with struct namelist 401 and struct typelist. */ 402 static int 403 ng_generic_list_getLength(const struct ng_parse_type *type, 404 const u_char *start, const u_char *buf) 405 { 406 return *((const u_int32_t *)(buf - 4)); 407 } 408 409 /* Get length of the array of struct linkinfo inside a struct hooklist */ 410 static int 411 ng_generic_linkinfo_getLength(const struct ng_parse_type *type, 412 const u_char *start, const u_char *buf) 413 { 414 const struct hooklist *hl = (const struct hooklist *)start; 415 416 return hl->nodeinfo.hooks; 417 } 418 419 /* Array type for a variable length array of struct namelist */ 420 static const struct ng_parse_array_info ng_nodeinfoarray_type_info = { 421 &ng_generic_nodeinfo_type, 422 &ng_generic_list_getLength 423 }; 424 static const struct ng_parse_type ng_generic_nodeinfoarray_type = { 425 &ng_parse_array_type, 426 &ng_nodeinfoarray_type_info 427 }; 428 429 /* Array type for a variable length array of struct typelist */ 430 static const struct ng_parse_array_info ng_typeinfoarray_type_info = { 431 &ng_generic_typeinfo_type, 432 &ng_generic_list_getLength 433 }; 434 static const struct ng_parse_type ng_generic_typeinfoarray_type = { 435 &ng_parse_array_type, 436 &ng_typeinfoarray_type_info 437 }; 438 439 /* Array type for array of struct linkinfo in struct hooklist */ 440 static const struct ng_parse_array_info ng_generic_linkinfo_array_type_info = { 441 &ng_generic_linkinfo_type, 442 &ng_generic_linkinfo_getLength 443 }; 444 static const struct ng_parse_type ng_generic_linkinfo_array_type = { 445 &ng_parse_array_type, 446 &ng_generic_linkinfo_array_type_info 447 }; 448 449 DEFINE_PARSE_STRUCT_TYPE(typelist, TYPELIST, (&ng_generic_nodeinfoarray_type)); 450 DEFINE_PARSE_STRUCT_TYPE(hooklist, HOOKLIST, 451 (&ng_generic_nodeinfo_type, &ng_generic_linkinfo_array_type)); 452 DEFINE_PARSE_STRUCT_TYPE(listnodes, LISTNODES, 453 (&ng_generic_nodeinfoarray_type)); 454 455 /* List of commands and how to convert arguments to/from ASCII */ 456 static const struct ng_cmdlist ng_generic_cmds[] = { 457 { 458 NGM_GENERIC_COOKIE, 459 NGM_SHUTDOWN, 460 "shutdown", 461 NULL, 462 NULL 463 }, 464 { 465 NGM_GENERIC_COOKIE, 466 NGM_MKPEER, 467 "mkpeer", 468 &ng_generic_mkpeer_type, 469 NULL 470 }, 471 { 472 NGM_GENERIC_COOKIE, 473 NGM_CONNECT, 474 "connect", 475 &ng_generic_connect_type, 476 NULL 477 }, 478 { 479 NGM_GENERIC_COOKIE, 480 NGM_NAME, 481 "name", 482 &ng_generic_name_type, 483 NULL 484 }, 485 { 486 NGM_GENERIC_COOKIE, 487 NGM_RMHOOK, 488 "rmhook", 489 &ng_generic_rmhook_type, 490 NULL 491 }, 492 { 493 NGM_GENERIC_COOKIE, 494 NGM_NODEINFO, 495 "nodeinfo", 496 NULL, 497 &ng_generic_nodeinfo_type 498 }, 499 { 500 NGM_GENERIC_COOKIE, 501 NGM_LISTHOOKS, 502 "listhooks", 503 NULL, 504 &ng_generic_hooklist_type 505 }, 506 { 507 NGM_GENERIC_COOKIE, 508 NGM_LISTNAMES, 509 "listnames", 510 NULL, 511 &ng_generic_listnodes_type /* same as NGM_LISTNODES */ 512 }, 513 { 514 NGM_GENERIC_COOKIE, 515 NGM_LISTNODES, 516 "listnodes", 517 NULL, 518 &ng_generic_listnodes_type 519 }, 520 { 521 NGM_GENERIC_COOKIE, 522 NGM_LISTTYPES, 523 "listtypes", 524 NULL, 525 &ng_generic_typeinfo_type 526 }, 527 { 528 NGM_GENERIC_COOKIE, 529 NGM_TEXT_CONFIG, 530 "textconfig", 531 NULL, 532 &ng_parse_string_type 533 }, 534 { 535 NGM_GENERIC_COOKIE, 536 NGM_TEXT_STATUS, 537 "textstatus", 538 NULL, 539 &ng_parse_string_type 540 }, 541 { 542 NGM_GENERIC_COOKIE, 543 NGM_ASCII2BINARY, 544 "ascii2binary", 545 &ng_parse_ng_mesg_type, 546 &ng_parse_ng_mesg_type 547 }, 548 { 549 NGM_GENERIC_COOKIE, 550 NGM_BINARY2ASCII, 551 "binary2ascii", 552 &ng_parse_ng_mesg_type, 553 &ng_parse_ng_mesg_type 554 }, 555 { 0 } 556 }; 557 558 /************************************************************************ 559 Node routines 560 ************************************************************************/ 561 562 /* 563 * Instantiate a node of the requested type 564 */ 565 int 566 ng_make_node(const char *typename, node_p *nodepp) 567 { 568 struct ng_type *type; 569 int error; 570 571 /* Check that the type makes sense */ 572 if (typename == NULL) { 573 TRAP_ERROR(); 574 return (EINVAL); 575 } 576 577 /* Locate the node type. If we fail we return. Do not try to load 578 * module. 579 */ 580 if ((type = ng_findtype(typename)) == NULL) 581 return (ENXIO); 582 583 /* 584 * If we have a constructor, then make the node and 585 * call the constructor to do type specific initialisation. 586 */ 587 if (type->constructor != NULL) { 588 if ((error = ng_make_node_common(type, nodepp)) == 0) { 589 if ((error = ((*type->constructor)(*nodepp)) != 0)) { 590 NG_NODE_UNREF(*nodepp); 591 } 592 } 593 } else { 594 /* 595 * Node has no constructor. We cannot ask for one 596 * to be made. It must be brought into existence by 597 * some external agency. The external agency should 598 * call ng_make_node_common() directly to get the 599 * netgraph part initialised. 600 */ 601 TRAP_ERROR(); 602 error = EINVAL; 603 } 604 return (error); 605 } 606 607 /* 608 * Generic node creation. Called by node initialisation for externally 609 * instantiated nodes (e.g. hardware, sockets, etc ). 610 * The returned node has a reference count of 1. 611 */ 612 int 613 ng_make_node_common(struct ng_type *type, node_p *nodepp) 614 { 615 node_p node; 616 617 /* Require the node type to have been already installed */ 618 if (ng_findtype(type->name) == NULL) { 619 TRAP_ERROR(); 620 return (EINVAL); 621 } 622 623 /* Make a node and try attach it to the type */ 624 NG_ALLOC_NODE(node); 625 if (node == NULL) { 626 TRAP_ERROR(); 627 return (ENOMEM); 628 } 629 node->nd_type = type; 630 NG_NODE_REF(node); /* note reference */ 631 type->refs++; 632 633 NG_QUEUE_LOCK_INIT(&node->nd_input_queue); 634 node->nd_input_queue.queue = NULL; 635 node->nd_input_queue.last = &node->nd_input_queue.queue; 636 node->nd_input_queue.q_flags = 0; 637 node->nd_input_queue.q_node = node; 638 639 /* Initialize hook list for new node */ 640 LIST_INIT(&node->nd_hooks); 641 642 /* Link us into the name hash. */ 643 mtx_lock(&ng_namehash_mtx); 644 LIST_INSERT_HEAD(&ng_name_hash[0], node, nd_nodes); 645 mtx_unlock(&ng_namehash_mtx); 646 647 /* get an ID and put us in the hash chain */ 648 mtx_lock(&ng_idhash_mtx); 649 for (;;) { /* wrap protection, even if silly */ 650 node_p node2 = NULL; 651 node->nd_ID = nextID++; /* 137/second for 1 year before wrap */ 652 653 /* Is there a problem with the new number? */ 654 NG_IDHASH_FIND(node->nd_ID, node2); /* already taken? */ 655 if ((node->nd_ID != 0) && (node2 == NULL)) { 656 break; 657 } 658 } 659 LIST_INSERT_HEAD(&ng_ID_hash[NG_IDHASH_FN(node->nd_ID)], 660 node, nd_idnodes); 661 mtx_unlock(&ng_idhash_mtx); 662 663 /* Done */ 664 *nodepp = node; 665 return (0); 666 } 667 668 /* 669 * Forceably start the shutdown process on a node. Either call 670 * its shutdown method, or do the default shutdown if there is 671 * no type-specific method. 672 * 673 * We can only be called from a shutdown message, so we know we have 674 * a writer lock, and therefore exclusive access. It also means 675 * that we should not be on the work queue, but we check anyhow. 676 * 677 * Persistent node types must have a type-specific method which 678 * allocates a new node in which case, this one is irretrievably going away, 679 * or cleans up anything it needs, and just makes the node valid again, 680 * in which case we allow the node to survive. 681 * 682 * XXX We need to think of how to tell a persistent node that we 683 * REALLY need to go away because the hardware has gone or we 684 * are rebooting.... etc. 685 */ 686 void 687 ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3) 688 { 689 hook_p hook; 690 691 /* Check if it's already shutting down */ 692 if ((node->nd_flags & NGF_CLOSING) != 0) 693 return; 694 695 if (node == &ng_deadnode) { 696 printf ("shutdown called on deadnode\n"); 697 return; 698 } 699 700 /* Add an extra reference so it doesn't go away during this */ 701 NG_NODE_REF(node); 702 703 /* 704 * Mark it invalid so any newcomers know not to try use it 705 * Also add our own mark so we can't recurse 706 * note that NGF_INVALID does not do this as it's also set during 707 * creation 708 */ 709 node->nd_flags |= NGF_INVALID|NGF_CLOSING; 710 711 /* If node has its pre-shutdown method, then call it first*/ 712 if (node->nd_type && node->nd_type->close) 713 (*node->nd_type->close)(node); 714 715 /* Notify all remaining connected nodes to disconnect */ 716 while ((hook = LIST_FIRST(&node->nd_hooks)) != NULL) 717 ng_destroy_hook(hook); 718 719 /* 720 * Drain the input queue forceably. 721 * it has no hooks so what's it going to do, bleed on someone? 722 * Theoretically we came here from a queue entry that was added 723 * Just before the queue was closed, so it should be empty anyway. 724 * Also removes us from worklist if needed. 725 */ 726 ng_flush_input_queue(&node->nd_input_queue); 727 728 /* Ask the type if it has anything to do in this case */ 729 if (node->nd_type && node->nd_type->shutdown) { 730 (*node->nd_type->shutdown)(node); 731 if (NG_NODE_IS_VALID(node)) { 732 /* 733 * Well, blow me down if the node code hasn't declared 734 * that it doesn't want to die. 735 * Presumably it is a persistant node. 736 * If we REALLY want it to go away, 737 * e.g. hardware going away, 738 * Our caller should set NGF_REALLY_DIE in nd_flags. 739 */ 740 node->nd_flags &= ~(NGF_INVALID|NGF_CLOSING); 741 NG_NODE_UNREF(node); /* Assume they still have theirs */ 742 return; 743 } 744 } else { /* do the default thing */ 745 NG_NODE_UNREF(node); 746 } 747 748 ng_unname(node); /* basically a NOP these days */ 749 750 /* 751 * Remove extra reference, possibly the last 752 * Possible other holders of references may include 753 * timeout callouts, but theoretically the node's supposed to 754 * have cancelled them. Possibly hardware dependencies may 755 * force a driver to 'linger' with a reference. 756 */ 757 NG_NODE_UNREF(node); 758 } 759 760 /* 761 * Remove a reference to the node, possibly the last. 762 * deadnode always acts as it it were the last. 763 */ 764 int 765 ng_unref_node(node_p node) 766 { 767 int v; 768 769 if (node == &ng_deadnode) { 770 return (0); 771 } 772 773 do { 774 v = node->nd_refs - 1; 775 } while (! atomic_cmpset_int(&node->nd_refs, v + 1, v)); 776 777 if (v == 0) { /* we were the last */ 778 779 mtx_lock(&ng_namehash_mtx); 780 node->nd_type->refs--; /* XXX maybe should get types lock? */ 781 LIST_REMOVE(node, nd_nodes); 782 mtx_unlock(&ng_namehash_mtx); 783 784 mtx_lock(&ng_idhash_mtx); 785 LIST_REMOVE(node, nd_idnodes); 786 mtx_unlock(&ng_idhash_mtx); 787 788 mtx_destroy(&node->nd_input_queue.q_mtx); 789 NG_FREE_NODE(node); 790 } 791 return (v); 792 } 793 794 /************************************************************************ 795 Node ID handling 796 ************************************************************************/ 797 static node_p 798 ng_ID2noderef(ng_ID_t ID) 799 { 800 node_p node; 801 mtx_lock(&ng_idhash_mtx); 802 NG_IDHASH_FIND(ID, node); 803 if(node) 804 NG_NODE_REF(node); 805 mtx_unlock(&ng_idhash_mtx); 806 return(node); 807 } 808 809 ng_ID_t 810 ng_node2ID(node_p node) 811 { 812 return (node ? NG_NODE_ID(node) : 0); 813 } 814 815 /************************************************************************ 816 Node name handling 817 ************************************************************************/ 818 819 /* 820 * Assign a node a name. Once assigned, the name cannot be changed. 821 */ 822 int 823 ng_name_node(node_p node, const char *name) 824 { 825 int i, hash; 826 node_p node2; 827 828 /* Check the name is valid */ 829 for (i = 0; i < NG_NODESIZ; i++) { 830 if (name[i] == '\0' || name[i] == '.' || name[i] == ':') 831 break; 832 } 833 if (i == 0 || name[i] != '\0') { 834 TRAP_ERROR(); 835 return (EINVAL); 836 } 837 if (ng_decodeidname(name) != 0) { /* valid IDs not allowed here */ 838 TRAP_ERROR(); 839 return (EINVAL); 840 } 841 842 /* Check the name isn't already being used */ 843 if ((node2 = ng_name2noderef(node, name)) != NULL) { 844 NG_NODE_UNREF(node2); 845 TRAP_ERROR(); 846 return (EADDRINUSE); 847 } 848 849 /* copy it */ 850 strlcpy(NG_NODE_NAME(node), name, NG_NODESIZ); 851 852 /* Update name hash. */ 853 NG_NAMEHASH(name, hash); 854 mtx_lock(&ng_namehash_mtx); 855 LIST_REMOVE(node, nd_nodes); 856 LIST_INSERT_HEAD(&ng_name_hash[hash], node, nd_nodes); 857 mtx_unlock(&ng_namehash_mtx); 858 859 return (0); 860 } 861 862 /* 863 * Find a node by absolute name. The name should NOT end with ':' 864 * The name "." means "this node" and "[xxx]" means "the node 865 * with ID (ie, at address) xxx". 866 * 867 * Returns the node if found, else NULL. 868 * Eventually should add something faster than a sequential search. 869 * Note it acquires a reference on the node so you can be sure it's still 870 * there. 871 */ 872 node_p 873 ng_name2noderef(node_p here, const char *name) 874 { 875 node_p node; 876 ng_ID_t temp; 877 int hash; 878 879 /* "." means "this node" */ 880 if (strcmp(name, ".") == 0) { 881 NG_NODE_REF(here); 882 return(here); 883 } 884 885 /* Check for name-by-ID */ 886 if ((temp = ng_decodeidname(name)) != 0) { 887 return (ng_ID2noderef(temp)); 888 } 889 890 /* Find node by name */ 891 NG_NAMEHASH(name, hash); 892 mtx_lock(&ng_namehash_mtx); 893 LIST_FOREACH(node, &ng_name_hash[hash], nd_nodes) { 894 if (NG_NODE_IS_VALID(node) && 895 (strcmp(NG_NODE_NAME(node), name) == 0)) { 896 break; 897 } 898 } 899 if (node) 900 NG_NODE_REF(node); 901 mtx_unlock(&ng_namehash_mtx); 902 return (node); 903 } 904 905 /* 906 * Decode an ID name, eg. "[f03034de]". Returns 0 if the 907 * string is not valid, otherwise returns the value. 908 */ 909 static ng_ID_t 910 ng_decodeidname(const char *name) 911 { 912 const int len = strlen(name); 913 char *eptr; 914 u_long val; 915 916 /* Check for proper length, brackets, no leading junk */ 917 if ((len < 3) 918 || (name[0] != '[') 919 || (name[len - 1] != ']') 920 || (!isxdigit(name[1]))) { 921 return ((ng_ID_t)0); 922 } 923 924 /* Decode number */ 925 val = strtoul(name + 1, &eptr, 16); 926 if ((eptr - name != len - 1) 927 || (val == ULONG_MAX) 928 || (val == 0)) { 929 return ((ng_ID_t)0); 930 } 931 return (ng_ID_t)val; 932 } 933 934 /* 935 * Remove a name from a node. This should only be called 936 * when shutting down and removing the node. 937 * IF we allow name changing this may be more resurrected. 938 */ 939 void 940 ng_unname(node_p node) 941 { 942 } 943 944 /************************************************************************ 945 Hook routines 946 Names are not optional. Hooks are always connected, except for a 947 brief moment within these routines. On invalidation or during creation 948 they are connected to the 'dead' hook. 949 ************************************************************************/ 950 951 /* 952 * Remove a hook reference 953 */ 954 void 955 ng_unref_hook(hook_p hook) 956 { 957 int v; 958 959 if (hook == &ng_deadhook) { 960 return; 961 } 962 do { 963 v = hook->hk_refs; 964 } while (! atomic_cmpset_int(&hook->hk_refs, v, v - 1)); 965 966 if (v == 1) { /* we were the last */ 967 if (_NG_HOOK_NODE(hook)) { /* it'll probably be ng_deadnode */ 968 _NG_NODE_UNREF((_NG_HOOK_NODE(hook))); 969 hook->hk_node = NULL; 970 } 971 NG_FREE_HOOK(hook); 972 } 973 } 974 975 /* 976 * Add an unconnected hook to a node. Only used internally. 977 * Assumes node is locked. (XXX not yet true ) 978 */ 979 static int 980 ng_add_hook(node_p node, const char *name, hook_p *hookp) 981 { 982 hook_p hook; 983 int error = 0; 984 985 /* Check that the given name is good */ 986 if (name == NULL) { 987 TRAP_ERROR(); 988 return (EINVAL); 989 } 990 if (ng_findhook(node, name) != NULL) { 991 TRAP_ERROR(); 992 return (EEXIST); 993 } 994 995 /* Allocate the hook and link it up */ 996 NG_ALLOC_HOOK(hook); 997 if (hook == NULL) { 998 TRAP_ERROR(); 999 return (ENOMEM); 1000 } 1001 hook->hk_refs = 1; /* add a reference for us to return */ 1002 hook->hk_flags = HK_INVALID; 1003 hook->hk_peer = &ng_deadhook; /* start off this way */ 1004 hook->hk_node = node; 1005 NG_NODE_REF(node); /* each hook counts as a reference */ 1006 1007 /* Set hook name */ 1008 strlcpy(NG_HOOK_NAME(hook), name, NG_HOOKSIZ); 1009 1010 /* 1011 * Check if the node type code has something to say about it 1012 * If it fails, the unref of the hook will also unref the node. 1013 */ 1014 if (node->nd_type->newhook != NULL) { 1015 if ((error = (*node->nd_type->newhook)(node, hook, name))) { 1016 NG_HOOK_UNREF(hook); /* this frees the hook */ 1017 return (error); 1018 } 1019 } 1020 /* 1021 * The 'type' agrees so far, so go ahead and link it in. 1022 * We'll ask again later when we actually connect the hooks. 1023 */ 1024 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks); 1025 node->nd_numhooks++; 1026 NG_HOOK_REF(hook); /* one for the node */ 1027 1028 if (hookp) 1029 *hookp = hook; 1030 return (0); 1031 } 1032 1033 /* 1034 * Find a hook 1035 * 1036 * Node types may supply their own optimized routines for finding 1037 * hooks. If none is supplied, we just do a linear search. 1038 * XXX Possibly we should add a reference to the hook? 1039 */ 1040 hook_p 1041 ng_findhook(node_p node, const char *name) 1042 { 1043 hook_p hook; 1044 1045 if (node->nd_type->findhook != NULL) 1046 return (*node->nd_type->findhook)(node, name); 1047 LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) { 1048 if (NG_HOOK_IS_VALID(hook) 1049 && (strcmp(NG_HOOK_NAME(hook), name) == 0)) 1050 return (hook); 1051 } 1052 return (NULL); 1053 } 1054 1055 /* 1056 * Destroy a hook 1057 * 1058 * As hooks are always attached, this really destroys two hooks. 1059 * The one given, and the one attached to it. Disconnect the hooks 1060 * from each other first. We reconnect the peer hook to the 'dead' 1061 * hook so that it can still exist after we depart. We then 1062 * send the peer its own destroy message. This ensures that we only 1063 * interact with the peer's structures when it is locked processing that 1064 * message. We hold a reference to the peer hook so we are guaranteed that 1065 * the peer hook and node are still going to exist until 1066 * we are finished there as the hook holds a ref on the node. 1067 * We run this same code again on the peer hook, but that time it is already 1068 * attached to the 'dead' hook. 1069 * 1070 * This routine is called at all stages of hook creation 1071 * on error detection and must be able to handle any such stage. 1072 */ 1073 void 1074 ng_destroy_hook(hook_p hook) 1075 { 1076 hook_p peer; 1077 node_p node; 1078 1079 if (hook == &ng_deadhook) { /* better safe than sorry */ 1080 printf("ng_destroy_hook called on deadhook\n"); 1081 return; 1082 } 1083 1084 /* 1085 * Protect divorce process with mutex, to avoid races on 1086 * simultaneous disconnect. 1087 */ 1088 mtx_lock(&ng_topo_mtx); 1089 1090 hook->hk_flags |= HK_INVALID; 1091 1092 peer = NG_HOOK_PEER(hook); 1093 node = NG_HOOK_NODE(hook); 1094 1095 if (peer && (peer != &ng_deadhook)) { 1096 /* 1097 * Set the peer to point to ng_deadhook 1098 * from this moment on we are effectively independent it. 1099 * send it an rmhook message of it's own. 1100 */ 1101 peer->hk_peer = &ng_deadhook; /* They no longer know us */ 1102 hook->hk_peer = &ng_deadhook; /* Nor us, them */ 1103 if (NG_HOOK_NODE(peer) == &ng_deadnode) { 1104 /* 1105 * If it's already divorced from a node, 1106 * just free it. 1107 */ 1108 mtx_unlock(&ng_topo_mtx); 1109 } else { 1110 mtx_unlock(&ng_topo_mtx); 1111 ng_rmhook_self(peer); /* Send it a surprise */ 1112 } 1113 NG_HOOK_UNREF(peer); /* account for peer link */ 1114 NG_HOOK_UNREF(hook); /* account for peer link */ 1115 } else 1116 mtx_unlock(&ng_topo_mtx); 1117 1118 mtx_assert(&ng_topo_mtx, MA_NOTOWNED); 1119 1120 /* 1121 * Remove the hook from the node's list to avoid possible recursion 1122 * in case the disconnection results in node shutdown. 1123 */ 1124 if (node == &ng_deadnode) { /* happens if called from ng_con_nodes() */ 1125 return; 1126 } 1127 LIST_REMOVE(hook, hk_hooks); 1128 node->nd_numhooks--; 1129 if (node->nd_type->disconnect) { 1130 /* 1131 * The type handler may elect to destroy the node so don't 1132 * trust its existence after this point. (except 1133 * that we still hold a reference on it. (which we 1134 * inherrited from the hook we are destroying) 1135 */ 1136 (*node->nd_type->disconnect) (hook); 1137 } 1138 1139 /* 1140 * Note that because we will point to ng_deadnode, the original node 1141 * is not decremented automatically so we do that manually. 1142 */ 1143 _NG_HOOK_NODE(hook) = &ng_deadnode; 1144 NG_NODE_UNREF(node); /* We no longer point to it so adjust count */ 1145 NG_HOOK_UNREF(hook); /* Account for linkage (in list) to node */ 1146 } 1147 1148 /* 1149 * Take two hooks on a node and merge the connection so that the given node 1150 * is effectively bypassed. 1151 */ 1152 int 1153 ng_bypass(hook_p hook1, hook_p hook2) 1154 { 1155 if (hook1->hk_node != hook2->hk_node) { 1156 TRAP_ERROR(); 1157 return (EINVAL); 1158 } 1159 hook1->hk_peer->hk_peer = hook2->hk_peer; 1160 hook2->hk_peer->hk_peer = hook1->hk_peer; 1161 1162 hook1->hk_peer = &ng_deadhook; 1163 hook2->hk_peer = &ng_deadhook; 1164 1165 NG_HOOK_UNREF(hook1); 1166 NG_HOOK_UNREF(hook2); 1167 1168 /* XXX If we ever cache methods on hooks update them as well */ 1169 ng_destroy_hook(hook1); 1170 ng_destroy_hook(hook2); 1171 return (0); 1172 } 1173 1174 /* 1175 * Install a new netgraph type 1176 */ 1177 int 1178 ng_newtype(struct ng_type *tp) 1179 { 1180 const size_t namelen = strlen(tp->name); 1181 1182 /* Check version and type name fields */ 1183 if ((tp->version != NG_ABI_VERSION) 1184 || (namelen == 0) 1185 || (namelen >= NG_TYPESIZ)) { 1186 TRAP_ERROR(); 1187 if (tp->version != NG_ABI_VERSION) { 1188 printf("Netgraph: Node type rejected. ABI mismatch. Suggest recompile\n"); 1189 } 1190 return (EINVAL); 1191 } 1192 1193 /* Check for name collision */ 1194 if (ng_findtype(tp->name) != NULL) { 1195 TRAP_ERROR(); 1196 return (EEXIST); 1197 } 1198 1199 1200 /* Link in new type */ 1201 mtx_lock(&ng_typelist_mtx); 1202 LIST_INSERT_HEAD(&ng_typelist, tp, types); 1203 tp->refs = 1; /* first ref is linked list */ 1204 mtx_unlock(&ng_typelist_mtx); 1205 return (0); 1206 } 1207 1208 /* 1209 * unlink a netgraph type 1210 * If no examples exist 1211 */ 1212 int 1213 ng_rmtype(struct ng_type *tp) 1214 { 1215 /* Check for name collision */ 1216 if (tp->refs != 1) { 1217 TRAP_ERROR(); 1218 return (EBUSY); 1219 } 1220 1221 /* Unlink type */ 1222 mtx_lock(&ng_typelist_mtx); 1223 LIST_REMOVE(tp, types); 1224 mtx_unlock(&ng_typelist_mtx); 1225 return (0); 1226 } 1227 1228 /* 1229 * Look for a type of the name given 1230 */ 1231 struct ng_type * 1232 ng_findtype(const char *typename) 1233 { 1234 struct ng_type *type; 1235 1236 mtx_lock(&ng_typelist_mtx); 1237 LIST_FOREACH(type, &ng_typelist, types) { 1238 if (strcmp(type->name, typename) == 0) 1239 break; 1240 } 1241 mtx_unlock(&ng_typelist_mtx); 1242 return (type); 1243 } 1244 1245 /************************************************************************ 1246 Composite routines 1247 ************************************************************************/ 1248 /* 1249 * Connect two nodes using the specified hooks, using queued functions. 1250 */ 1251 static int 1252 ng_con_part3(node_p node, item_p item, hook_p hook) 1253 { 1254 int error = 0; 1255 1256 /* 1257 * When we run, we know that the node 'node' is locked for us. 1258 * Our caller has a reference on the hook. 1259 * Our caller has a reference on the node. 1260 * (In this case our caller is ng_apply_item() ). 1261 * The peer hook has a reference on the hook. 1262 * We are all set up except for the final call to the node, and 1263 * the clearing of the INVALID flag. 1264 */ 1265 if (NG_HOOK_NODE(hook) == &ng_deadnode) { 1266 /* 1267 * The node must have been freed again since we last visited 1268 * here. ng_destry_hook() has this effect but nothing else does. 1269 * We should just release our references and 1270 * free anything we can think of. 1271 * Since we know it's been destroyed, and it's our caller 1272 * that holds the references, just return. 1273 */ 1274 ERROUT(ENOENT); 1275 } 1276 if (hook->hk_node->nd_type->connect) { 1277 if ((error = (*hook->hk_node->nd_type->connect) (hook))) { 1278 ng_destroy_hook(hook); /* also zaps peer */ 1279 printf("failed in ng_con_part3()\n"); 1280 ERROUT(error); 1281 } 1282 } 1283 /* 1284 * XXX this is wrong for SMP. Possibly we need 1285 * to separate out 'create' and 'invalid' flags. 1286 * should only set flags on hooks we have locked under our node. 1287 */ 1288 hook->hk_flags &= ~HK_INVALID; 1289 done: 1290 NG_FREE_ITEM(item); 1291 return (error); 1292 } 1293 1294 static int 1295 ng_con_part2(node_p node, item_p item, hook_p hook) 1296 { 1297 hook_p peer; 1298 int error = 0; 1299 1300 /* 1301 * When we run, we know that the node 'node' is locked for us. 1302 * Our caller has a reference on the hook. 1303 * Our caller has a reference on the node. 1304 * (In this case our caller is ng_apply_item() ). 1305 * The peer hook has a reference on the hook. 1306 * our node pointer points to the 'dead' node. 1307 * First check the hook name is unique. 1308 * Should not happen because we checked before queueing this. 1309 */ 1310 if (ng_findhook(node, NG_HOOK_NAME(hook)) != NULL) { 1311 TRAP_ERROR(); 1312 ng_destroy_hook(hook); /* should destroy peer too */ 1313 printf("failed in ng_con_part2()\n"); 1314 ERROUT(EEXIST); 1315 } 1316 /* 1317 * Check if the node type code has something to say about it 1318 * If it fails, the unref of the hook will also unref the attached node, 1319 * however since that node is 'ng_deadnode' this will do nothing. 1320 * The peer hook will also be destroyed. 1321 */ 1322 if (node->nd_type->newhook != NULL) { 1323 if ((error = (*node->nd_type->newhook)(node, hook, 1324 hook->hk_name))) { 1325 ng_destroy_hook(hook); /* should destroy peer too */ 1326 printf("failed in ng_con_part2()\n"); 1327 ERROUT(error); 1328 } 1329 } 1330 1331 /* 1332 * The 'type' agrees so far, so go ahead and link it in. 1333 * We'll ask again later when we actually connect the hooks. 1334 */ 1335 hook->hk_node = node; /* just overwrite ng_deadnode */ 1336 NG_NODE_REF(node); /* each hook counts as a reference */ 1337 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks); 1338 node->nd_numhooks++; 1339 NG_HOOK_REF(hook); /* one for the node */ 1340 1341 /* 1342 * We now have a symmetrical situation, where both hooks have been 1343 * linked to their nodes, the newhook methods have been called 1344 * And the references are all correct. The hooks are still marked 1345 * as invalid, as we have not called the 'connect' methods 1346 * yet. 1347 * We can call the local one immediately as we have the 1348 * node locked, but we need to queue the remote one. 1349 */ 1350 if (hook->hk_node->nd_type->connect) { 1351 if ((error = (*hook->hk_node->nd_type->connect) (hook))) { 1352 ng_destroy_hook(hook); /* also zaps peer */ 1353 printf("failed in ng_con_part2(A)\n"); 1354 ERROUT(error); 1355 } 1356 } 1357 1358 /* 1359 * Acquire topo mutex to avoid race with ng_destroy_hook(). 1360 */ 1361 mtx_lock(&ng_topo_mtx); 1362 peer = hook->hk_peer; 1363 if (peer == &ng_deadhook) { 1364 mtx_unlock(&ng_topo_mtx); 1365 printf("failed in ng_con_part2(B)\n"); 1366 ng_destroy_hook(hook); 1367 ERROUT(ENOENT); 1368 } 1369 mtx_unlock(&ng_topo_mtx); 1370 1371 if ((error = ng_send_fn2(peer->hk_node, peer, item, &ng_con_part3, 1372 NULL, 0, NG_REUSE_ITEM))) { 1373 printf("failed in ng_con_part2(C)\n"); 1374 ng_destroy_hook(hook); /* also zaps peer */ 1375 return (error); /* item was consumed. */ 1376 } 1377 hook->hk_flags &= ~HK_INVALID; /* need both to be able to work */ 1378 return (0); /* item was consumed. */ 1379 done: 1380 NG_FREE_ITEM(item); 1381 return (error); 1382 } 1383 1384 /* 1385 * Connect this node with another node. We assume that this node is 1386 * currently locked, as we are only called from an NGM_CONNECT message. 1387 */ 1388 static int 1389 ng_con_nodes(item_p item, node_p node, const char *name, 1390 node_p node2, const char *name2) 1391 { 1392 int error; 1393 hook_p hook; 1394 hook_p hook2; 1395 1396 if (ng_findhook(node2, name2) != NULL) { 1397 return(EEXIST); 1398 } 1399 if ((error = ng_add_hook(node, name, &hook))) /* gives us a ref */ 1400 return (error); 1401 /* Allocate the other hook and link it up */ 1402 NG_ALLOC_HOOK(hook2); 1403 if (hook2 == NULL) { 1404 TRAP_ERROR(); 1405 ng_destroy_hook(hook); /* XXX check ref counts so far */ 1406 NG_HOOK_UNREF(hook); /* including our ref */ 1407 return (ENOMEM); 1408 } 1409 hook2->hk_refs = 1; /* start with a reference for us. */ 1410 hook2->hk_flags = HK_INVALID; 1411 hook2->hk_peer = hook; /* Link the two together */ 1412 hook->hk_peer = hook2; 1413 NG_HOOK_REF(hook); /* Add a ref for the peer to each*/ 1414 NG_HOOK_REF(hook2); 1415 hook2->hk_node = &ng_deadnode; 1416 strlcpy(NG_HOOK_NAME(hook2), name2, NG_HOOKSIZ); 1417 1418 /* 1419 * Queue the function above. 1420 * Procesing continues in that function in the lock context of 1421 * the other node. 1422 */ 1423 if ((error = ng_send_fn2(node2, hook2, item, &ng_con_part2, NULL, 0, 1424 NG_NOFLAGS))) { 1425 printf("failed in ng_con_nodes(): %d\n", error); 1426 ng_destroy_hook(hook); /* also zaps peer */ 1427 } 1428 1429 NG_HOOK_UNREF(hook); /* Let each hook go if it wants to */ 1430 NG_HOOK_UNREF(hook2); 1431 return (error); 1432 } 1433 1434 /* 1435 * Make a peer and connect. 1436 * We assume that the local node is locked. 1437 * The new node probably doesn't need a lock until 1438 * it has a hook, because it cannot really have any work until then, 1439 * but we should think about it a bit more. 1440 * 1441 * The problem may come if the other node also fires up 1442 * some hardware or a timer or some other source of activation, 1443 * also it may already get a command msg via it's ID. 1444 * 1445 * We could use the same method as ng_con_nodes() but we'd have 1446 * to add ability to remove the node when failing. (Not hard, just 1447 * make arg1 point to the node to remove). 1448 * Unless of course we just ignore failure to connect and leave 1449 * an unconnected node? 1450 */ 1451 static int 1452 ng_mkpeer(node_p node, const char *name, const char *name2, char *type) 1453 { 1454 node_p node2; 1455 hook_p hook1, hook2; 1456 int error; 1457 1458 if ((error = ng_make_node(type, &node2))) { 1459 return (error); 1460 } 1461 1462 if ((error = ng_add_hook(node, name, &hook1))) { /* gives us a ref */ 1463 ng_rmnode(node2, NULL, NULL, 0); 1464 return (error); 1465 } 1466 1467 if ((error = ng_add_hook(node2, name2, &hook2))) { 1468 ng_rmnode(node2, NULL, NULL, 0); 1469 ng_destroy_hook(hook1); 1470 NG_HOOK_UNREF(hook1); 1471 return (error); 1472 } 1473 1474 /* 1475 * Actually link the two hooks together. 1476 */ 1477 hook1->hk_peer = hook2; 1478 hook2->hk_peer = hook1; 1479 1480 /* Each hook is referenced by the other */ 1481 NG_HOOK_REF(hook1); 1482 NG_HOOK_REF(hook2); 1483 1484 /* Give each node the opportunity to veto the pending connection */ 1485 if (hook1->hk_node->nd_type->connect) { 1486 error = (*hook1->hk_node->nd_type->connect) (hook1); 1487 } 1488 1489 if ((error == 0) && hook2->hk_node->nd_type->connect) { 1490 error = (*hook2->hk_node->nd_type->connect) (hook2); 1491 1492 } 1493 1494 /* 1495 * drop the references we were holding on the two hooks. 1496 */ 1497 if (error) { 1498 ng_destroy_hook(hook2); /* also zaps hook1 */ 1499 ng_rmnode(node2, NULL, NULL, 0); 1500 } else { 1501 /* As a last act, allow the hooks to be used */ 1502 hook1->hk_flags &= ~HK_INVALID; 1503 hook2->hk_flags &= ~HK_INVALID; 1504 } 1505 NG_HOOK_UNREF(hook1); 1506 NG_HOOK_UNREF(hook2); 1507 return (error); 1508 } 1509 1510 /************************************************************************ 1511 Utility routines to send self messages 1512 ************************************************************************/ 1513 1514 /* Shut this node down as soon as everyone is clear of it */ 1515 /* Should add arg "immediately" to jump the queue */ 1516 int 1517 ng_rmnode_self(node_p node) 1518 { 1519 int error; 1520 1521 if (node == &ng_deadnode) 1522 return (0); 1523 node->nd_flags |= NGF_INVALID; 1524 if (node->nd_flags & NGF_CLOSING) 1525 return (0); 1526 1527 error = ng_send_fn(node, NULL, &ng_rmnode, NULL, 0); 1528 return (error); 1529 } 1530 1531 static void 1532 ng_rmhook_part2(node_p node, hook_p hook, void *arg1, int arg2) 1533 { 1534 ng_destroy_hook(hook); 1535 return ; 1536 } 1537 1538 int 1539 ng_rmhook_self(hook_p hook) 1540 { 1541 int error; 1542 node_p node = NG_HOOK_NODE(hook); 1543 1544 if (node == &ng_deadnode) 1545 return (0); 1546 1547 error = ng_send_fn(node, hook, &ng_rmhook_part2, NULL, 0); 1548 return (error); 1549 } 1550 1551 /*********************************************************************** 1552 * Parse and verify a string of the form: <NODE:><PATH> 1553 * 1554 * Such a string can refer to a specific node or a specific hook 1555 * on a specific node, depending on how you look at it. In the 1556 * latter case, the PATH component must not end in a dot. 1557 * 1558 * Both <NODE:> and <PATH> are optional. The <PATH> is a string 1559 * of hook names separated by dots. This breaks out the original 1560 * string, setting *nodep to "NODE" (or NULL if none) and *pathp 1561 * to "PATH" (or NULL if degenerate). Also, *hookp will point to 1562 * the final hook component of <PATH>, if any, otherwise NULL. 1563 * 1564 * This returns -1 if the path is malformed. The char ** are optional. 1565 ***********************************************************************/ 1566 int 1567 ng_path_parse(char *addr, char **nodep, char **pathp, char **hookp) 1568 { 1569 char *node, *path, *hook; 1570 int k; 1571 1572 /* 1573 * Extract absolute NODE, if any 1574 */ 1575 for (path = addr; *path && *path != ':'; path++); 1576 if (*path) { 1577 node = addr; /* Here's the NODE */ 1578 *path++ = '\0'; /* Here's the PATH */ 1579 1580 /* Node name must not be empty */ 1581 if (!*node) 1582 return -1; 1583 1584 /* A name of "." is OK; otherwise '.' not allowed */ 1585 if (strcmp(node, ".") != 0) { 1586 for (k = 0; node[k]; k++) 1587 if (node[k] == '.') 1588 return -1; 1589 } 1590 } else { 1591 node = NULL; /* No absolute NODE */ 1592 path = addr; /* Here's the PATH */ 1593 } 1594 1595 /* Snoop for illegal characters in PATH */ 1596 for (k = 0; path[k]; k++) 1597 if (path[k] == ':') 1598 return -1; 1599 1600 /* Check for no repeated dots in PATH */ 1601 for (k = 0; path[k]; k++) 1602 if (path[k] == '.' && path[k + 1] == '.') 1603 return -1; 1604 1605 /* Remove extra (degenerate) dots from beginning or end of PATH */ 1606 if (path[0] == '.') 1607 path++; 1608 if (*path && path[strlen(path) - 1] == '.') 1609 path[strlen(path) - 1] = 0; 1610 1611 /* If PATH has a dot, then we're not talking about a hook */ 1612 if (*path) { 1613 for (hook = path, k = 0; path[k]; k++) 1614 if (path[k] == '.') { 1615 hook = NULL; 1616 break; 1617 } 1618 } else 1619 path = hook = NULL; 1620 1621 /* Done */ 1622 if (nodep) 1623 *nodep = node; 1624 if (pathp) 1625 *pathp = path; 1626 if (hookp) 1627 *hookp = hook; 1628 return (0); 1629 } 1630 1631 /* 1632 * Given a path, which may be absolute or relative, and a starting node, 1633 * return the destination node. 1634 */ 1635 int 1636 ng_path2noderef(node_p here, const char *address, 1637 node_p *destp, hook_p *lasthook) 1638 { 1639 char fullpath[NG_PATHSIZ]; 1640 char *nodename, *path, pbuf[2]; 1641 node_p node, oldnode; 1642 char *cp; 1643 hook_p hook = NULL; 1644 1645 /* Initialize */ 1646 if (destp == NULL) { 1647 TRAP_ERROR(); 1648 return EINVAL; 1649 } 1650 *destp = NULL; 1651 1652 /* Make a writable copy of address for ng_path_parse() */ 1653 strncpy(fullpath, address, sizeof(fullpath) - 1); 1654 fullpath[sizeof(fullpath) - 1] = '\0'; 1655 1656 /* Parse out node and sequence of hooks */ 1657 if (ng_path_parse(fullpath, &nodename, &path, NULL) < 0) { 1658 TRAP_ERROR(); 1659 return EINVAL; 1660 } 1661 if (path == NULL) { 1662 pbuf[0] = '.'; /* Needs to be writable */ 1663 pbuf[1] = '\0'; 1664 path = pbuf; 1665 } 1666 1667 /* 1668 * For an absolute address, jump to the starting node. 1669 * Note that this holds a reference on the node for us. 1670 * Don't forget to drop the reference if we don't need it. 1671 */ 1672 if (nodename) { 1673 node = ng_name2noderef(here, nodename); 1674 if (node == NULL) { 1675 TRAP_ERROR(); 1676 return (ENOENT); 1677 } 1678 } else { 1679 if (here == NULL) { 1680 TRAP_ERROR(); 1681 return (EINVAL); 1682 } 1683 node = here; 1684 NG_NODE_REF(node); 1685 } 1686 1687 /* 1688 * Now follow the sequence of hooks 1689 * XXX 1690 * We actually cannot guarantee that the sequence 1691 * is not being demolished as we crawl along it 1692 * without extra-ordinary locking etc. 1693 * So this is a bit dodgy to say the least. 1694 * We can probably hold up some things by holding 1695 * the nodelist mutex for the time of this 1696 * crawl if we wanted.. At least that way we wouldn't have to 1697 * worry about the nodes disappearing, but the hooks would still 1698 * be a problem. 1699 */ 1700 for (cp = path; node != NULL && *cp != '\0'; ) { 1701 char *segment; 1702 1703 /* 1704 * Break out the next path segment. Replace the dot we just 1705 * found with a NUL; "cp" points to the next segment (or the 1706 * NUL at the end). 1707 */ 1708 for (segment = cp; *cp != '\0'; cp++) { 1709 if (*cp == '.') { 1710 *cp++ = '\0'; 1711 break; 1712 } 1713 } 1714 1715 /* Empty segment */ 1716 if (*segment == '\0') 1717 continue; 1718 1719 /* We have a segment, so look for a hook by that name */ 1720 hook = ng_findhook(node, segment); 1721 1722 /* Can't get there from here... */ 1723 if (hook == NULL 1724 || NG_HOOK_PEER(hook) == NULL 1725 || NG_HOOK_NOT_VALID(hook) 1726 || NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))) { 1727 TRAP_ERROR(); 1728 NG_NODE_UNREF(node); 1729 #if 0 1730 printf("hooknotvalid %s %s %d %d %d %d ", 1731 path, 1732 segment, 1733 hook == NULL, 1734 NG_HOOK_PEER(hook) == NULL, 1735 NG_HOOK_NOT_VALID(hook), 1736 NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))); 1737 #endif 1738 return (ENOENT); 1739 } 1740 1741 /* 1742 * Hop on over to the next node 1743 * XXX 1744 * Big race conditions here as hooks and nodes go away 1745 * *** Idea.. store an ng_ID_t in each hook and use that 1746 * instead of the direct hook in this crawl? 1747 */ 1748 oldnode = node; 1749 if ((node = NG_PEER_NODE(hook))) 1750 NG_NODE_REF(node); /* XXX RACE */ 1751 NG_NODE_UNREF(oldnode); /* XXX another race */ 1752 if (NG_NODE_NOT_VALID(node)) { 1753 NG_NODE_UNREF(node); /* XXX more races */ 1754 node = NULL; 1755 } 1756 } 1757 1758 /* If node somehow missing, fail here (probably this is not needed) */ 1759 if (node == NULL) { 1760 TRAP_ERROR(); 1761 return (ENXIO); 1762 } 1763 1764 /* Done */ 1765 *destp = node; 1766 if (lasthook != NULL) 1767 *lasthook = (hook ? NG_HOOK_PEER(hook) : NULL); 1768 return (0); 1769 } 1770 1771 /***************************************************************\ 1772 * Input queue handling. 1773 * All activities are submitted to the node via the input queue 1774 * which implements a multiple-reader/single-writer gate. 1775 * Items which cannot be handled immediately are queued. 1776 * 1777 * read-write queue locking inline functions * 1778 \***************************************************************/ 1779 1780 static __inline item_p ng_dequeue(struct ng_queue * ngq, int *rw); 1781 static __inline item_p ng_acquire_read(struct ng_queue * ngq, 1782 item_p item); 1783 static __inline item_p ng_acquire_write(struct ng_queue * ngq, 1784 item_p item); 1785 static __inline void ng_leave_read(struct ng_queue * ngq); 1786 static __inline void ng_leave_write(struct ng_queue * ngq); 1787 static __inline void ng_queue_rw(struct ng_queue * ngq, 1788 item_p item, int rw); 1789 1790 /* 1791 * Definition of the bits fields in the ng_queue flag word. 1792 * Defined here rather than in netgraph.h because no-one should fiddle 1793 * with them. 1794 * 1795 * The ordering here may be important! don't shuffle these. 1796 */ 1797 /*- 1798 Safety Barrier--------+ (adjustable to suit taste) (not used yet) 1799 | 1800 V 1801 +-------+-------+-------+-------+-------+-------+-------+-------+ 1802 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 1803 | |A|c|t|i|v|e| |R|e|a|d|e|r| |C|o|u|n|t| | | | | | | | | |P|A| 1804 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |O|W| 1805 +-------+-------+-------+-------+-------+-------+-------+-------+ 1806 \___________________________ ____________________________/ | | 1807 V | | 1808 [active reader count] | | 1809 | | 1810 Operation Pending -------------------------------+ | 1811 | 1812 Active Writer ---------------------------------------+ 1813 1814 1815 */ 1816 #define WRITER_ACTIVE 0x00000001 1817 #define OP_PENDING 0x00000002 1818 #define READER_INCREMENT 0x00000004 1819 #define READER_MASK 0xfffffffc /* Not valid if WRITER_ACTIVE is set */ 1820 #define SAFETY_BARRIER 0x00100000 /* 128K items queued should be enough */ 1821 1822 /* Defines of more elaborate states on the queue */ 1823 /* Mask of bits a new read cares about */ 1824 #define NGQ_RMASK (WRITER_ACTIVE|OP_PENDING) 1825 1826 /* Mask of bits a new write cares about */ 1827 #define NGQ_WMASK (NGQ_RMASK|READER_MASK) 1828 1829 /* Test to decide if there is something on the queue. */ 1830 #define QUEUE_ACTIVE(QP) ((QP)->q_flags & OP_PENDING) 1831 1832 /* How to decide what the next queued item is. */ 1833 #define HEAD_IS_READER(QP) NGI_QUEUED_READER((QP)->queue) 1834 #define HEAD_IS_WRITER(QP) NGI_QUEUED_WRITER((QP)->queue) /* notused */ 1835 1836 /* Read the status to decide if the next item on the queue can now run. */ 1837 #define QUEUED_READER_CAN_PROCEED(QP) \ 1838 (((QP)->q_flags & (NGQ_RMASK & ~OP_PENDING)) == 0) 1839 #define QUEUED_WRITER_CAN_PROCEED(QP) \ 1840 (((QP)->q_flags & (NGQ_WMASK & ~OP_PENDING)) == 0) 1841 1842 /* Is there a chance of getting ANY work off the queue? */ 1843 #define NEXT_QUEUED_ITEM_CAN_PROCEED(QP) \ 1844 (QUEUE_ACTIVE(QP) && \ 1845 ((HEAD_IS_READER(QP)) ? QUEUED_READER_CAN_PROCEED(QP) : \ 1846 QUEUED_WRITER_CAN_PROCEED(QP))) 1847 1848 1849 #define NGQRW_R 0 1850 #define NGQRW_W 1 1851 1852 /* 1853 * Taking into account the current state of the queue and node, possibly take 1854 * the next entry off the queue and return it. Return NULL if there was 1855 * nothing we could return, either because there really was nothing there, or 1856 * because the node was in a state where it cannot yet process the next item 1857 * on the queue. 1858 * 1859 * This MUST MUST MUST be called with the mutex held. 1860 */ 1861 static __inline item_p 1862 ng_dequeue(struct ng_queue *ngq, int *rw) 1863 { 1864 item_p item; 1865 u_int add_arg; 1866 1867 mtx_assert(&ngq->q_mtx, MA_OWNED); 1868 /* 1869 * If there is nothing queued, then just return. 1870 * No point in continuing. 1871 * XXXGL: assert this? 1872 */ 1873 if (!QUEUE_ACTIVE(ngq)) { 1874 CTR4(KTR_NET, "%20s: node [%x] (%p) queue empty; " 1875 "queue flags 0x%lx", __func__, 1876 ngq->q_node->nd_ID, ngq->q_node, ngq->q_flags); 1877 return (NULL); 1878 } 1879 1880 /* 1881 * From here, we can assume there is a head item. 1882 * We need to find out what it is and if it can be dequeued, given 1883 * the current state of the node. 1884 */ 1885 if (HEAD_IS_READER(ngq)) { 1886 if (!QUEUED_READER_CAN_PROCEED(ngq)) { 1887 /* 1888 * It's a reader but we can't use it. 1889 * We are stalled so make sure we don't 1890 * get called again until something changes. 1891 */ 1892 ng_worklist_remove(ngq->q_node); 1893 CTR4(KTR_NET, "%20s: node [%x] (%p) queued reader " 1894 "can't proceed; queue flags 0x%lx", __func__, 1895 ngq->q_node->nd_ID, ngq->q_node, ngq->q_flags); 1896 return (NULL); 1897 } 1898 /* 1899 * Head of queue is a reader and we have no write active. 1900 * We don't care how many readers are already active. 1901 * Add the correct increment for the reader count. 1902 */ 1903 add_arg = READER_INCREMENT; 1904 *rw = NGQRW_R; 1905 } else if (QUEUED_WRITER_CAN_PROCEED(ngq)) { 1906 /* 1907 * There is a pending write, no readers and no active writer. 1908 * This means we can go ahead with the pending writer. Note 1909 * the fact that we now have a writer, ready for when we take 1910 * it off the queue. 1911 * 1912 * We don't need to worry about a possible collision with the 1913 * fasttrack reader. 1914 * 1915 * The fasttrack thread may take a long time to discover that we 1916 * are running so we would have an inconsistent state in the 1917 * flags for a while. Since we ignore the reader count 1918 * entirely when the WRITER_ACTIVE flag is set, this should 1919 * not matter (in fact it is defined that way). If it tests 1920 * the flag before this operation, the OP_PENDING flag 1921 * will make it fail, and if it tests it later, the 1922 * WRITER_ACTIVE flag will do the same. If it is SO slow that 1923 * we have actually completed the operation, and neither flag 1924 * is set by the time that it tests the flags, then it is 1925 * actually ok for it to continue. If it completes and we've 1926 * finished and the read pending is set it still fails. 1927 * 1928 * So we can just ignore it, as long as we can ensure that the 1929 * transition from WRITE_PENDING state to the WRITER_ACTIVE 1930 * state is atomic. 1931 * 1932 * After failing, first it will be held back by the mutex, then 1933 * when it can proceed, it will queue its request, then it 1934 * would arrive at this function. Usually it will have to 1935 * leave empty handed because the ACTIVE WRITER bit will be 1936 * set. 1937 * 1938 * Adjust the flags for the new active writer. 1939 */ 1940 add_arg = WRITER_ACTIVE; 1941 *rw = NGQRW_W; 1942 /* 1943 * We want to write "active writer, no readers " Now go make 1944 * it true. In fact there may be a number in the readers 1945 * count but we know it is not true and will be fixed soon. 1946 * We will fix the flags for the next pending entry in a 1947 * moment. 1948 */ 1949 } else { 1950 /* 1951 * We can't dequeue anything.. return and say so. Probably we 1952 * have a write pending and the readers count is non zero. If 1953 * we got here because a reader hit us just at the wrong 1954 * moment with the fasttrack code, and put us in a strange 1955 * state, then it will be coming through in just a moment, 1956 * (just as soon as we release the mutex) and keep things 1957 * moving. 1958 * Make sure we remove ourselves from the work queue. It 1959 * would be a waste of effort to do all this again. 1960 */ 1961 ng_worklist_remove(ngq->q_node); 1962 CTR4(KTR_NET, "%20s: node [%x] (%p) can't dequeue anything; " 1963 "queue flags 0x%lx", __func__, 1964 ngq->q_node->nd_ID, ngq->q_node, ngq->q_flags); 1965 return (NULL); 1966 } 1967 1968 /* 1969 * Now we dequeue the request (whatever it may be) and correct the 1970 * pending flags and the next and last pointers. 1971 */ 1972 item = ngq->queue; 1973 ngq->queue = item->el_next; 1974 CTR6(KTR_NET, "%20s: node [%x] (%p) dequeued item %p with flags 0x%lx; " 1975 "queue flags 0x%lx", __func__, 1976 ngq->q_node->nd_ID,ngq->q_node, item, item->el_flags, ngq->q_flags); 1977 if (ngq->last == &(item->el_next)) { 1978 /* 1979 * that was the last entry in the queue so set the 'last 1980 * pointer up correctly and make sure the pending flag is 1981 * clear. 1982 */ 1983 add_arg += -OP_PENDING; 1984 ngq->last = &(ngq->queue); 1985 /* 1986 * Whatever flag was set will be cleared and 1987 * the new acive field will be set by the add as well, 1988 * so we don't need to change add_arg. 1989 * But we know we don't need to be on the work list. 1990 */ 1991 atomic_add_long(&ngq->q_flags, add_arg); 1992 ng_worklist_remove(ngq->q_node); 1993 } else { 1994 /* 1995 * Since there is still something on the queue 1996 * we don't need to change the PENDING flag. 1997 */ 1998 atomic_add_long(&ngq->q_flags, add_arg); 1999 /* 2000 * If we see more doable work, make sure we are 2001 * on the work queue. 2002 */ 2003 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq)) { 2004 ng_setisr(ngq->q_node); 2005 } 2006 } 2007 CTR6(KTR_NET, "%20s: node [%x] (%p) returning item %p as %s; " 2008 "queue flags 0x%lx", __func__, 2009 ngq->q_node->nd_ID, ngq->q_node, item, *rw ? "WRITER" : "READER" , 2010 ngq->q_flags); 2011 return (item); 2012 } 2013 2014 /* 2015 * Queue a packet to be picked up by someone else. 2016 * We really don't care who, but we can't or don't want to hang around 2017 * to process it ourselves. We are probably an interrupt routine.. 2018 * If the queue could be run, flag the netisr handler to start. 2019 */ 2020 static __inline void 2021 ng_queue_rw(struct ng_queue * ngq, item_p item, int rw) 2022 { 2023 mtx_assert(&ngq->q_mtx, MA_OWNED); 2024 2025 if (rw == NGQRW_W) 2026 NGI_SET_WRITER(item); 2027 else 2028 NGI_SET_READER(item); 2029 item->el_next = NULL; /* maybe not needed */ 2030 *ngq->last = item; 2031 CTR5(KTR_NET, "%20s: node [%x] (%p) queued item %p as %s", __func__, 2032 ngq->q_node->nd_ID, ngq->q_node, item, rw ? "WRITER" : "READER" ); 2033 /* 2034 * If it was the first item in the queue then we need to 2035 * set the last pointer and the type flags. 2036 */ 2037 if (ngq->last == &(ngq->queue)) { 2038 atomic_add_long(&ngq->q_flags, OP_PENDING); 2039 CTR3(KTR_NET, "%20s: node [%x] (%p) set OP_PENDING", __func__, 2040 ngq->q_node->nd_ID, ngq->q_node); 2041 } 2042 2043 ngq->last = &(item->el_next); 2044 /* 2045 * We can take the worklist lock with the node locked 2046 * BUT NOT THE REVERSE! 2047 */ 2048 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq)) 2049 ng_setisr(ngq->q_node); 2050 } 2051 2052 2053 /* 2054 * This function 'cheats' in that it first tries to 'grab' the use of the 2055 * node, without going through the mutex. We can do this becasue of the 2056 * semantics of the lock. The semantics include a clause that says that the 2057 * value of the readers count is invalid if the WRITER_ACTIVE flag is set. It 2058 * also says that the WRITER_ACTIVE flag cannot be set if the readers count 2059 * is not zero. Note that this talks about what is valid to SET the 2060 * WRITER_ACTIVE flag, because from the moment it is set, the value if the 2061 * reader count is immaterial, and not valid. The two 'pending' flags have a 2062 * similar effect, in that If they are orthogonal to the two active fields in 2063 * how they are set, but if either is set, the attempted 'grab' need to be 2064 * backed out because there is earlier work, and we maintain ordering in the 2065 * queue. The result of this is that the reader request can try obtain use of 2066 * the node with only a single atomic addition, and without any of the mutex 2067 * overhead. If this fails the operation degenerates to the same as for other 2068 * cases. 2069 * 2070 */ 2071 static __inline item_p 2072 ng_acquire_read(struct ng_queue *ngq, item_p item) 2073 { 2074 KASSERT(ngq != &ng_deadnode.nd_input_queue, 2075 ("%s: working on deadnode", __func__)); 2076 2077 /* ######### Hack alert ######### */ 2078 atomic_add_long(&ngq->q_flags, READER_INCREMENT); 2079 if ((ngq->q_flags & NGQ_RMASK) == 0) { 2080 /* Successfully grabbed node */ 2081 CTR4(KTR_NET, "%20s: node [%x] (%p) fast acquired item %p", 2082 __func__, ngq->q_node->nd_ID, ngq->q_node, item); 2083 return (item); 2084 } 2085 /* undo the damage if we didn't succeed */ 2086 atomic_subtract_long(&ngq->q_flags, READER_INCREMENT); 2087 2088 /* ######### End Hack alert ######### */ 2089 NG_QUEUE_LOCK(ngq); 2090 /* 2091 * Try again. Another processor (or interrupt for that matter) may 2092 * have removed the last queued item that was stopping us from 2093 * running, between the previous test, and the moment that we took 2094 * the mutex. (Or maybe a writer completed.) 2095 * Even if another fast-track reader hits during this period 2096 * we don't care as multiple readers is OK. 2097 */ 2098 if ((ngq->q_flags & NGQ_RMASK) == 0) { 2099 atomic_add_long(&ngq->q_flags, READER_INCREMENT); 2100 NG_QUEUE_UNLOCK(ngq); 2101 CTR4(KTR_NET, "%20s: node [%x] (%p) slow acquired item %p", 2102 __func__, ngq->q_node->nd_ID, ngq->q_node, item); 2103 return (item); 2104 } 2105 2106 /* 2107 * and queue the request for later. 2108 */ 2109 ng_queue_rw(ngq, item, NGQRW_R); 2110 NG_QUEUE_UNLOCK(ngq); 2111 2112 return (NULL); 2113 } 2114 2115 static __inline item_p 2116 ng_acquire_write(struct ng_queue *ngq, item_p item) 2117 { 2118 KASSERT(ngq != &ng_deadnode.nd_input_queue, 2119 ("%s: working on deadnode", __func__)); 2120 2121 restart: 2122 NG_QUEUE_LOCK(ngq); 2123 /* 2124 * If there are no readers, no writer, and no pending packets, then 2125 * we can just go ahead. In all other situations we need to queue the 2126 * request 2127 */ 2128 if ((ngq->q_flags & NGQ_WMASK) == 0) { 2129 /* collision could happen *HERE* */ 2130 atomic_add_long(&ngq->q_flags, WRITER_ACTIVE); 2131 NG_QUEUE_UNLOCK(ngq); 2132 if (ngq->q_flags & READER_MASK) { 2133 /* Collision with fast-track reader */ 2134 atomic_subtract_long(&ngq->q_flags, WRITER_ACTIVE); 2135 goto restart; 2136 } 2137 CTR4(KTR_NET, "%20s: node [%x] (%p) acquired item %p", 2138 __func__, ngq->q_node->nd_ID, ngq->q_node, item); 2139 return (item); 2140 } 2141 2142 /* 2143 * and queue the request for later. 2144 */ 2145 ng_queue_rw(ngq, item, NGQRW_W); 2146 NG_QUEUE_UNLOCK(ngq); 2147 2148 return (NULL); 2149 } 2150 2151 #if 0 2152 static __inline item_p 2153 ng_upgrade_write(struct ng_queue *ngq, item_p item) 2154 { 2155 KASSERT(ngq != &ng_deadnode.nd_input_queue, 2156 ("%s: working on deadnode", __func__)); 2157 2158 NGI_SET_WRITER(item); 2159 2160 mtx_lock_spin(&(ngq->q_mtx)); 2161 2162 /* 2163 * There will never be no readers as we are there ourselves. 2164 * Set the WRITER_ACTIVE flags ASAP to block out fast track readers. 2165 * The caller we are running from will call ng_leave_read() 2166 * soon, so we must account for that. We must leave again with the 2167 * READER lock. If we find other readers, then 2168 * queue the request for later. However "later" may be rignt now 2169 * if there are no readers. We don't really care if there are queued 2170 * items as we will bypass them anyhow. 2171 */ 2172 atomic_add_long(&ngq->q_flags, WRITER_ACTIVE - READER_INCREMENT); 2173 if (ngq->q_flags & (NGQ_WMASK & ~OP_PENDING) == WRITER_ACTIVE) { 2174 mtx_unlock_spin(&(ngq->q_mtx)); 2175 2176 /* It's just us, act on the item. */ 2177 /* will NOT drop writer lock when done */ 2178 ng_apply_item(node, item, 0); 2179 2180 /* 2181 * Having acted on the item, atomically 2182 * down grade back to READER and finish up 2183 */ 2184 atomic_add_long(&ngq->q_flags, 2185 READER_INCREMENT - WRITER_ACTIVE); 2186 2187 /* Our caller will call ng_leave_read() */ 2188 return; 2189 } 2190 /* 2191 * It's not just us active, so queue us AT THE HEAD. 2192 * "Why?" I hear you ask. 2193 * Put us at the head of the queue as we've already been 2194 * through it once. If there is nothing else waiting, 2195 * set the correct flags. 2196 */ 2197 if ((item->el_next = ngq->queue) == NULL) { 2198 /* 2199 * Set up the "last" pointer. 2200 * We are the only (and thus last) item 2201 */ 2202 ngq->last = &(item->el_next); 2203 2204 /* We've gone from, 0 to 1 item in the queue */ 2205 atomic_add_long(&ngq->q_flags, OP_PENDING); 2206 2207 CTR3(KTR_NET, "%20s: node [%x] (%p) set OP_PENDING", __func__, 2208 ngq->q_node->nd_ID, ngq->q_node); 2209 }; 2210 ngq->queue = item; 2211 CTR5(KTR_NET, "%20s: node [%x] (%p) requeued item %p as WRITER", 2212 __func__, ngq->q_node->nd_ID, ngq->q_node, item ); 2213 2214 /* Reverse what we did above. That downgrades us back to reader */ 2215 atomic_add_long(&ngq->q_flags, READER_INCREMENT - WRITER_ACTIVE); 2216 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq)) 2217 ng_setisr(ngq->q_node); 2218 mtx_unlock_spin(&(ngq->q_mtx)); 2219 2220 return; 2221 } 2222 2223 #endif 2224 2225 static __inline void 2226 ng_leave_read(struct ng_queue *ngq) 2227 { 2228 atomic_subtract_long(&ngq->q_flags, READER_INCREMENT); 2229 } 2230 2231 static __inline void 2232 ng_leave_write(struct ng_queue *ngq) 2233 { 2234 atomic_subtract_long(&ngq->q_flags, WRITER_ACTIVE); 2235 } 2236 2237 static void 2238 ng_flush_input_queue(struct ng_queue * ngq) 2239 { 2240 item_p item; 2241 2242 NG_QUEUE_LOCK(ngq); 2243 while (ngq->queue) { 2244 item = ngq->queue; 2245 ngq->queue = item->el_next; 2246 if (ngq->last == &(item->el_next)) { 2247 ngq->last = &(ngq->queue); 2248 atomic_add_long(&ngq->q_flags, -OP_PENDING); 2249 } 2250 NG_QUEUE_UNLOCK(ngq); 2251 2252 /* If the item is supplying a callback, call it with an error */ 2253 if (item->apply != NULL && 2254 refcount_release(&item->apply->refs)) { 2255 (*item->apply->apply)(item->apply->context, ENOENT); 2256 } 2257 NG_FREE_ITEM(item); 2258 NG_QUEUE_LOCK(ngq); 2259 } 2260 /* 2261 * Take us off the work queue if we are there. 2262 * We definately have no work to be done. 2263 */ 2264 ng_worklist_remove(ngq->q_node); 2265 NG_QUEUE_UNLOCK(ngq); 2266 } 2267 2268 /*********************************************************************** 2269 * Externally visible method for sending or queueing messages or data. 2270 ***********************************************************************/ 2271 2272 /* 2273 * The module code should have filled out the item correctly by this stage: 2274 * Common: 2275 * reference to destination node. 2276 * Reference to destination rcv hook if relevant. 2277 * apply pointer must be or NULL or reference valid struct ng_apply_info. 2278 * Data: 2279 * pointer to mbuf 2280 * Control_Message: 2281 * pointer to msg. 2282 * ID of original sender node. (return address) 2283 * Function: 2284 * Function pointer 2285 * void * argument 2286 * integer argument 2287 * 2288 * The nodes have several routines and macros to help with this task: 2289 */ 2290 2291 int 2292 ng_snd_item(item_p item, int flags) 2293 { 2294 hook_p hook; 2295 node_p node; 2296 int queue, rw; 2297 struct ng_queue *ngq; 2298 int error = 0; 2299 2300 /* We are sending item, so it must be present! */ 2301 KASSERT(item != NULL, ("ng_snd_item: item is NULL")); 2302 2303 #ifdef NETGRAPH_DEBUG 2304 _ngi_check(item, __FILE__, __LINE__); 2305 #endif 2306 2307 /* Item was sent once more, postpone apply() call. */ 2308 if (item->apply) 2309 refcount_acquire(&item->apply->refs); 2310 2311 node = NGI_NODE(item); 2312 /* Node is never optional. */ 2313 KASSERT(node != NULL, ("ng_snd_item: node is NULL")); 2314 2315 hook = NGI_HOOK(item); 2316 /* Valid hook and mbuf are mandatory for data. */ 2317 if ((item->el_flags & NGQF_TYPE) == NGQF_DATA) { 2318 KASSERT(hook != NULL, ("ng_snd_item: hook for data is NULL")); 2319 if (NGI_M(item) == NULL) 2320 ERROUT(EINVAL); 2321 CHECK_DATA_MBUF(NGI_M(item)); 2322 } 2323 2324 /* 2325 * If the item or the node specifies single threading, force 2326 * writer semantics. Similarly, the node may say one hook always 2327 * produces writers. These are overrides. 2328 */ 2329 if (((item->el_flags & NGQF_RW) == NGQF_WRITER) || 2330 (node->nd_flags & NGF_FORCE_WRITER) || 2331 (hook && (hook->hk_flags & HK_FORCE_WRITER))) { 2332 rw = NGQRW_W; 2333 } else { 2334 rw = NGQRW_R; 2335 } 2336 2337 /* 2338 * If sender or receiver requests queued delivery or stack usage 2339 * level is dangerous - enqueue message. 2340 */ 2341 if ((flags & NG_QUEUE) || (hook && (hook->hk_flags & HK_QUEUE))) { 2342 queue = 1; 2343 } else { 2344 queue = 0; 2345 #ifdef GET_STACK_USAGE 2346 /* 2347 * Most of netgraph nodes have small stack consumption and 2348 * for them 25% of free stack space is more than enough. 2349 * Nodes/hooks with higher stack usage should be marked as 2350 * HI_STACK. For them 50% of stack will be guaranteed then. 2351 * XXX: Values 25% and 50% are completely empirical. 2352 */ 2353 size_t st, su, sl; 2354 GET_STACK_USAGE(st, su); 2355 sl = st - su; 2356 if ((sl * 4 < st) || 2357 ((sl * 2 < st) && ((node->nd_flags & NGF_HI_STACK) || 2358 (hook && (hook->hk_flags & HK_HI_STACK))))) { 2359 queue = 1; 2360 } 2361 #endif 2362 } 2363 2364 ngq = &node->nd_input_queue; 2365 if (queue) { 2366 /* Put it on the queue for that node*/ 2367 #ifdef NETGRAPH_DEBUG 2368 _ngi_check(item, __FILE__, __LINE__); 2369 #endif 2370 NG_QUEUE_LOCK(ngq); 2371 ng_queue_rw(ngq, item, rw); 2372 NG_QUEUE_UNLOCK(ngq); 2373 2374 return ((flags & NG_PROGRESS) ? EINPROGRESS : 0); 2375 } 2376 2377 /* 2378 * We already decided how we will be queueud or treated. 2379 * Try get the appropriate operating permission. 2380 */ 2381 if (rw == NGQRW_R) 2382 item = ng_acquire_read(ngq, item); 2383 else 2384 item = ng_acquire_write(ngq, item); 2385 2386 2387 /* Item was queued while trying to get permission. */ 2388 if (item == NULL) 2389 return ((flags & NG_PROGRESS) ? EINPROGRESS : 0); 2390 2391 #ifdef NETGRAPH_DEBUG 2392 _ngi_check(item, __FILE__, __LINE__); 2393 #endif 2394 2395 NGI_GET_NODE(item, node); /* zaps stored node */ 2396 2397 error = ng_apply_item(node, item, rw); /* drops r/w lock when done */ 2398 2399 /* 2400 * If the node goes away when we remove the reference, 2401 * whatever we just did caused it.. whatever we do, DO NOT 2402 * access the node again! 2403 */ 2404 if (NG_NODE_UNREF(node) == 0) 2405 return (error); 2406 2407 NG_QUEUE_LOCK(ngq); 2408 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq)) 2409 ng_setisr(ngq->q_node); 2410 NG_QUEUE_UNLOCK(ngq); 2411 2412 return (error); 2413 2414 done: 2415 /* If was not sent, apply callback here. */ 2416 if (item->apply != NULL && refcount_release(&item->apply->refs)) 2417 (*item->apply->apply)(item->apply->context, error); 2418 2419 NG_FREE_ITEM(item); 2420 return (error); 2421 } 2422 2423 /* 2424 * We have an item that was possibly queued somewhere. 2425 * It should contain all the information needed 2426 * to run it on the appropriate node/hook. 2427 * If there is apply pointer and we own the last reference, call apply(). 2428 */ 2429 static int 2430 ng_apply_item(node_p node, item_p item, int rw) 2431 { 2432 hook_p hook; 2433 int error = 0; 2434 ng_rcvdata_t *rcvdata; 2435 ng_rcvmsg_t *rcvmsg; 2436 struct ng_apply_info *apply; 2437 2438 /* Node and item are never optional. */ 2439 KASSERT(node != NULL, ("ng_apply_item: node is NULL")); 2440 KASSERT(item != NULL, ("ng_apply_item: item is NULL")); 2441 2442 NGI_GET_HOOK(item, hook); /* clears stored hook */ 2443 #ifdef NETGRAPH_DEBUG 2444 _ngi_check(item, __FILE__, __LINE__); 2445 #endif 2446 2447 apply = item->apply; 2448 2449 switch (item->el_flags & NGQF_TYPE) { 2450 case NGQF_DATA: 2451 /* 2452 * Check things are still ok as when we were queued. 2453 */ 2454 KASSERT(hook != NULL, ("ng_apply_item: hook for data is NULL")); 2455 if (NG_HOOK_NOT_VALID(hook) || 2456 NG_NODE_NOT_VALID(node)) { 2457 error = EIO; 2458 NG_FREE_ITEM(item); 2459 break; 2460 } 2461 /* 2462 * If no receive method, just silently drop it. 2463 * Give preference to the hook over-ride method 2464 */ 2465 if ((!(rcvdata = hook->hk_rcvdata)) 2466 && (!(rcvdata = NG_HOOK_NODE(hook)->nd_type->rcvdata))) { 2467 error = 0; 2468 NG_FREE_ITEM(item); 2469 break; 2470 } 2471 error = (*rcvdata)(hook, item); 2472 break; 2473 case NGQF_MESG: 2474 if (hook && NG_HOOK_NOT_VALID(hook)) { 2475 /* 2476 * The hook has been zapped then we can't use it. 2477 * Immediately drop its reference. 2478 * The message may not need it. 2479 */ 2480 NG_HOOK_UNREF(hook); 2481 hook = NULL; 2482 } 2483 /* 2484 * Similarly, if the node is a zombie there is 2485 * nothing we can do with it, drop everything. 2486 */ 2487 if (NG_NODE_NOT_VALID(node)) { 2488 TRAP_ERROR(); 2489 error = EINVAL; 2490 NG_FREE_ITEM(item); 2491 break; 2492 } 2493 /* 2494 * Call the appropriate message handler for the object. 2495 * It is up to the message handler to free the message. 2496 * If it's a generic message, handle it generically, 2497 * otherwise call the type's message handler (if it exists). 2498 * XXX (race). Remember that a queued message may 2499 * reference a node or hook that has just been 2500 * invalidated. It will exist as the queue code 2501 * is holding a reference, but.. 2502 */ 2503 if ((NGI_MSG(item)->header.typecookie == NGM_GENERIC_COOKIE) && 2504 ((NGI_MSG(item)->header.flags & NGF_RESP) == 0)) { 2505 error = ng_generic_msg(node, item, hook); 2506 break; 2507 } 2508 if (((!hook) || (!(rcvmsg = hook->hk_rcvmsg))) && 2509 (!(rcvmsg = node->nd_type->rcvmsg))) { 2510 TRAP_ERROR(); 2511 error = 0; 2512 NG_FREE_ITEM(item); 2513 break; 2514 } 2515 error = (*rcvmsg)(node, item, hook); 2516 break; 2517 case NGQF_FN: 2518 case NGQF_FN2: 2519 /* 2520 * We have to implicitly trust the hook, 2521 * as some of these are used for system purposes 2522 * where the hook is invalid. In the case of 2523 * the shutdown message we allow it to hit 2524 * even if the node is invalid. 2525 */ 2526 if ((NG_NODE_NOT_VALID(node)) 2527 && (NGI_FN(item) != &ng_rmnode)) { 2528 TRAP_ERROR(); 2529 error = EINVAL; 2530 NG_FREE_ITEM(item); 2531 break; 2532 } 2533 if ((item->el_flags & NGQF_TYPE) == NGQF_FN) { 2534 (*NGI_FN(item))(node, hook, NGI_ARG1(item), 2535 NGI_ARG2(item)); 2536 NG_FREE_ITEM(item); 2537 } else /* it is NGQF_FN2 */ 2538 error = (*NGI_FN2(item))(node, item, hook); 2539 break; 2540 } 2541 /* 2542 * We held references on some of the resources 2543 * that we took from the item. Now that we have 2544 * finished doing everything, drop those references. 2545 */ 2546 if (hook) 2547 NG_HOOK_UNREF(hook); 2548 2549 if (rw == NGQRW_R) 2550 ng_leave_read(&node->nd_input_queue); 2551 else 2552 ng_leave_write(&node->nd_input_queue); 2553 2554 /* Apply callback. */ 2555 if (apply != NULL && refcount_release(&apply->refs)) 2556 (*apply->apply)(apply->context, error); 2557 2558 return (error); 2559 } 2560 2561 /*********************************************************************** 2562 * Implement the 'generic' control messages 2563 ***********************************************************************/ 2564 static int 2565 ng_generic_msg(node_p here, item_p item, hook_p lasthook) 2566 { 2567 int error = 0; 2568 struct ng_mesg *msg; 2569 struct ng_mesg *resp = NULL; 2570 2571 NGI_GET_MSG(item, msg); 2572 if (msg->header.typecookie != NGM_GENERIC_COOKIE) { 2573 TRAP_ERROR(); 2574 error = EINVAL; 2575 goto out; 2576 } 2577 switch (msg->header.cmd) { 2578 case NGM_SHUTDOWN: 2579 ng_rmnode(here, NULL, NULL, 0); 2580 break; 2581 case NGM_MKPEER: 2582 { 2583 struct ngm_mkpeer *const mkp = (struct ngm_mkpeer *) msg->data; 2584 2585 if (msg->header.arglen != sizeof(*mkp)) { 2586 TRAP_ERROR(); 2587 error = EINVAL; 2588 break; 2589 } 2590 mkp->type[sizeof(mkp->type) - 1] = '\0'; 2591 mkp->ourhook[sizeof(mkp->ourhook) - 1] = '\0'; 2592 mkp->peerhook[sizeof(mkp->peerhook) - 1] = '\0'; 2593 error = ng_mkpeer(here, mkp->ourhook, mkp->peerhook, mkp->type); 2594 break; 2595 } 2596 case NGM_CONNECT: 2597 { 2598 struct ngm_connect *const con = 2599 (struct ngm_connect *) msg->data; 2600 node_p node2; 2601 2602 if (msg->header.arglen != sizeof(*con)) { 2603 TRAP_ERROR(); 2604 error = EINVAL; 2605 break; 2606 } 2607 con->path[sizeof(con->path) - 1] = '\0'; 2608 con->ourhook[sizeof(con->ourhook) - 1] = '\0'; 2609 con->peerhook[sizeof(con->peerhook) - 1] = '\0'; 2610 /* Don't forget we get a reference.. */ 2611 error = ng_path2noderef(here, con->path, &node2, NULL); 2612 if (error) 2613 break; 2614 error = ng_con_nodes(item, here, con->ourhook, 2615 node2, con->peerhook); 2616 NG_NODE_UNREF(node2); 2617 break; 2618 } 2619 case NGM_NAME: 2620 { 2621 struct ngm_name *const nam = (struct ngm_name *) msg->data; 2622 2623 if (msg->header.arglen != sizeof(*nam)) { 2624 TRAP_ERROR(); 2625 error = EINVAL; 2626 break; 2627 } 2628 nam->name[sizeof(nam->name) - 1] = '\0'; 2629 error = ng_name_node(here, nam->name); 2630 break; 2631 } 2632 case NGM_RMHOOK: 2633 { 2634 struct ngm_rmhook *const rmh = (struct ngm_rmhook *) msg->data; 2635 hook_p hook; 2636 2637 if (msg->header.arglen != sizeof(*rmh)) { 2638 TRAP_ERROR(); 2639 error = EINVAL; 2640 break; 2641 } 2642 rmh->ourhook[sizeof(rmh->ourhook) - 1] = '\0'; 2643 if ((hook = ng_findhook(here, rmh->ourhook)) != NULL) 2644 ng_destroy_hook(hook); 2645 break; 2646 } 2647 case NGM_NODEINFO: 2648 { 2649 struct nodeinfo *ni; 2650 2651 NG_MKRESPONSE(resp, msg, sizeof(*ni), M_NOWAIT); 2652 if (resp == NULL) { 2653 error = ENOMEM; 2654 break; 2655 } 2656 2657 /* Fill in node info */ 2658 ni = (struct nodeinfo *) resp->data; 2659 if (NG_NODE_HAS_NAME(here)) 2660 strcpy(ni->name, NG_NODE_NAME(here)); 2661 strcpy(ni->type, here->nd_type->name); 2662 ni->id = ng_node2ID(here); 2663 ni->hooks = here->nd_numhooks; 2664 break; 2665 } 2666 case NGM_LISTHOOKS: 2667 { 2668 const int nhooks = here->nd_numhooks; 2669 struct hooklist *hl; 2670 struct nodeinfo *ni; 2671 hook_p hook; 2672 2673 /* Get response struct */ 2674 NG_MKRESPONSE(resp, msg, sizeof(*hl) 2675 + (nhooks * sizeof(struct linkinfo)), M_NOWAIT); 2676 if (resp == NULL) { 2677 error = ENOMEM; 2678 break; 2679 } 2680 hl = (struct hooklist *) resp->data; 2681 ni = &hl->nodeinfo; 2682 2683 /* Fill in node info */ 2684 if (NG_NODE_HAS_NAME(here)) 2685 strcpy(ni->name, NG_NODE_NAME(here)); 2686 strcpy(ni->type, here->nd_type->name); 2687 ni->id = ng_node2ID(here); 2688 2689 /* Cycle through the linked list of hooks */ 2690 ni->hooks = 0; 2691 LIST_FOREACH(hook, &here->nd_hooks, hk_hooks) { 2692 struct linkinfo *const link = &hl->link[ni->hooks]; 2693 2694 if (ni->hooks >= nhooks) { 2695 log(LOG_ERR, "%s: number of %s changed\n", 2696 __func__, "hooks"); 2697 break; 2698 } 2699 if (NG_HOOK_NOT_VALID(hook)) 2700 continue; 2701 strcpy(link->ourhook, NG_HOOK_NAME(hook)); 2702 strcpy(link->peerhook, NG_PEER_HOOK_NAME(hook)); 2703 if (NG_PEER_NODE_NAME(hook)[0] != '\0') 2704 strcpy(link->nodeinfo.name, 2705 NG_PEER_NODE_NAME(hook)); 2706 strcpy(link->nodeinfo.type, 2707 NG_PEER_NODE(hook)->nd_type->name); 2708 link->nodeinfo.id = ng_node2ID(NG_PEER_NODE(hook)); 2709 link->nodeinfo.hooks = NG_PEER_NODE(hook)->nd_numhooks; 2710 ni->hooks++; 2711 } 2712 break; 2713 } 2714 2715 case NGM_LISTNAMES: 2716 case NGM_LISTNODES: 2717 { 2718 const int unnamed = (msg->header.cmd == NGM_LISTNODES); 2719 struct namelist *nl; 2720 node_p node; 2721 int num = 0, i; 2722 2723 mtx_lock(&ng_namehash_mtx); 2724 /* Count number of nodes */ 2725 for (i = 0; i < NG_NAME_HASH_SIZE; i++) { 2726 LIST_FOREACH(node, &ng_name_hash[i], nd_nodes) { 2727 if (NG_NODE_IS_VALID(node) && 2728 (unnamed || NG_NODE_HAS_NAME(node))) { 2729 num++; 2730 } 2731 } 2732 } 2733 mtx_unlock(&ng_namehash_mtx); 2734 2735 /* Get response struct */ 2736 NG_MKRESPONSE(resp, msg, sizeof(*nl) 2737 + (num * sizeof(struct nodeinfo)), M_NOWAIT); 2738 if (resp == NULL) { 2739 error = ENOMEM; 2740 break; 2741 } 2742 nl = (struct namelist *) resp->data; 2743 2744 /* Cycle through the linked list of nodes */ 2745 nl->numnames = 0; 2746 mtx_lock(&ng_namehash_mtx); 2747 for (i = 0; i < NG_NAME_HASH_SIZE; i++) { 2748 LIST_FOREACH(node, &ng_name_hash[i], nd_nodes) { 2749 struct nodeinfo *const np = 2750 &nl->nodeinfo[nl->numnames]; 2751 2752 if (NG_NODE_NOT_VALID(node)) 2753 continue; 2754 if (!unnamed && (! NG_NODE_HAS_NAME(node))) 2755 continue; 2756 if (nl->numnames >= num) { 2757 log(LOG_ERR, "%s: number of nodes changed\n", 2758 __func__); 2759 break; 2760 } 2761 if (NG_NODE_HAS_NAME(node)) 2762 strcpy(np->name, NG_NODE_NAME(node)); 2763 strcpy(np->type, node->nd_type->name); 2764 np->id = ng_node2ID(node); 2765 np->hooks = node->nd_numhooks; 2766 nl->numnames++; 2767 } 2768 } 2769 mtx_unlock(&ng_namehash_mtx); 2770 break; 2771 } 2772 2773 case NGM_LISTTYPES: 2774 { 2775 struct typelist *tl; 2776 struct ng_type *type; 2777 int num = 0; 2778 2779 mtx_lock(&ng_typelist_mtx); 2780 /* Count number of types */ 2781 LIST_FOREACH(type, &ng_typelist, types) { 2782 num++; 2783 } 2784 mtx_unlock(&ng_typelist_mtx); 2785 2786 /* Get response struct */ 2787 NG_MKRESPONSE(resp, msg, sizeof(*tl) 2788 + (num * sizeof(struct typeinfo)), M_NOWAIT); 2789 if (resp == NULL) { 2790 error = ENOMEM; 2791 break; 2792 } 2793 tl = (struct typelist *) resp->data; 2794 2795 /* Cycle through the linked list of types */ 2796 tl->numtypes = 0; 2797 mtx_lock(&ng_typelist_mtx); 2798 LIST_FOREACH(type, &ng_typelist, types) { 2799 struct typeinfo *const tp = &tl->typeinfo[tl->numtypes]; 2800 2801 if (tl->numtypes >= num) { 2802 log(LOG_ERR, "%s: number of %s changed\n", 2803 __func__, "types"); 2804 break; 2805 } 2806 strcpy(tp->type_name, type->name); 2807 tp->numnodes = type->refs - 1; /* don't count list */ 2808 tl->numtypes++; 2809 } 2810 mtx_unlock(&ng_typelist_mtx); 2811 break; 2812 } 2813 2814 case NGM_BINARY2ASCII: 2815 { 2816 int bufSize = 20 * 1024; /* XXX hard coded constant */ 2817 const struct ng_parse_type *argstype; 2818 const struct ng_cmdlist *c; 2819 struct ng_mesg *binary, *ascii; 2820 2821 /* Data area must contain a valid netgraph message */ 2822 binary = (struct ng_mesg *)msg->data; 2823 if (msg->header.arglen < sizeof(struct ng_mesg) || 2824 (msg->header.arglen - sizeof(struct ng_mesg) < 2825 binary->header.arglen)) { 2826 TRAP_ERROR(); 2827 error = EINVAL; 2828 break; 2829 } 2830 2831 /* Get a response message with lots of room */ 2832 NG_MKRESPONSE(resp, msg, sizeof(*ascii) + bufSize, M_NOWAIT); 2833 if (resp == NULL) { 2834 error = ENOMEM; 2835 break; 2836 } 2837 ascii = (struct ng_mesg *)resp->data; 2838 2839 /* Copy binary message header to response message payload */ 2840 bcopy(binary, ascii, sizeof(*binary)); 2841 2842 /* Find command by matching typecookie and command number */ 2843 for (c = here->nd_type->cmdlist; 2844 c != NULL && c->name != NULL; c++) { 2845 if (binary->header.typecookie == c->cookie 2846 && binary->header.cmd == c->cmd) 2847 break; 2848 } 2849 if (c == NULL || c->name == NULL) { 2850 for (c = ng_generic_cmds; c->name != NULL; c++) { 2851 if (binary->header.typecookie == c->cookie 2852 && binary->header.cmd == c->cmd) 2853 break; 2854 } 2855 if (c->name == NULL) { 2856 NG_FREE_MSG(resp); 2857 error = ENOSYS; 2858 break; 2859 } 2860 } 2861 2862 /* Convert command name to ASCII */ 2863 snprintf(ascii->header.cmdstr, sizeof(ascii->header.cmdstr), 2864 "%s", c->name); 2865 2866 /* Convert command arguments to ASCII */ 2867 argstype = (binary->header.flags & NGF_RESP) ? 2868 c->respType : c->mesgType; 2869 if (argstype == NULL) { 2870 *ascii->data = '\0'; 2871 } else { 2872 if ((error = ng_unparse(argstype, 2873 (u_char *)binary->data, 2874 ascii->data, bufSize)) != 0) { 2875 NG_FREE_MSG(resp); 2876 break; 2877 } 2878 } 2879 2880 /* Return the result as struct ng_mesg plus ASCII string */ 2881 bufSize = strlen(ascii->data) + 1; 2882 ascii->header.arglen = bufSize; 2883 resp->header.arglen = sizeof(*ascii) + bufSize; 2884 break; 2885 } 2886 2887 case NGM_ASCII2BINARY: 2888 { 2889 int bufSize = 2000; /* XXX hard coded constant */ 2890 const struct ng_cmdlist *c; 2891 const struct ng_parse_type *argstype; 2892 struct ng_mesg *ascii, *binary; 2893 int off = 0; 2894 2895 /* Data area must contain at least a struct ng_mesg + '\0' */ 2896 ascii = (struct ng_mesg *)msg->data; 2897 if ((msg->header.arglen < sizeof(*ascii) + 1) || 2898 (ascii->header.arglen < 1) || 2899 (msg->header.arglen < sizeof(*ascii) + 2900 ascii->header.arglen)) { 2901 TRAP_ERROR(); 2902 error = EINVAL; 2903 break; 2904 } 2905 ascii->data[ascii->header.arglen - 1] = '\0'; 2906 2907 /* Get a response message with lots of room */ 2908 NG_MKRESPONSE(resp, msg, sizeof(*binary) + bufSize, M_NOWAIT); 2909 if (resp == NULL) { 2910 error = ENOMEM; 2911 break; 2912 } 2913 binary = (struct ng_mesg *)resp->data; 2914 2915 /* Copy ASCII message header to response message payload */ 2916 bcopy(ascii, binary, sizeof(*ascii)); 2917 2918 /* Find command by matching ASCII command string */ 2919 for (c = here->nd_type->cmdlist; 2920 c != NULL && c->name != NULL; c++) { 2921 if (strcmp(ascii->header.cmdstr, c->name) == 0) 2922 break; 2923 } 2924 if (c == NULL || c->name == NULL) { 2925 for (c = ng_generic_cmds; c->name != NULL; c++) { 2926 if (strcmp(ascii->header.cmdstr, c->name) == 0) 2927 break; 2928 } 2929 if (c->name == NULL) { 2930 NG_FREE_MSG(resp); 2931 error = ENOSYS; 2932 break; 2933 } 2934 } 2935 2936 /* Convert command name to binary */ 2937 binary->header.cmd = c->cmd; 2938 binary->header.typecookie = c->cookie; 2939 2940 /* Convert command arguments to binary */ 2941 argstype = (binary->header.flags & NGF_RESP) ? 2942 c->respType : c->mesgType; 2943 if (argstype == NULL) { 2944 bufSize = 0; 2945 } else { 2946 if ((error = ng_parse(argstype, ascii->data, 2947 &off, (u_char *)binary->data, &bufSize)) != 0) { 2948 NG_FREE_MSG(resp); 2949 break; 2950 } 2951 } 2952 2953 /* Return the result */ 2954 binary->header.arglen = bufSize; 2955 resp->header.arglen = sizeof(*binary) + bufSize; 2956 break; 2957 } 2958 2959 case NGM_TEXT_CONFIG: 2960 case NGM_TEXT_STATUS: 2961 /* 2962 * This one is tricky as it passes the command down to the 2963 * actual node, even though it is a generic type command. 2964 * This means we must assume that the item/msg is already freed 2965 * when control passes back to us. 2966 */ 2967 if (here->nd_type->rcvmsg != NULL) { 2968 NGI_MSG(item) = msg; /* put it back as we found it */ 2969 return((*here->nd_type->rcvmsg)(here, item, lasthook)); 2970 } 2971 /* Fall through if rcvmsg not supported */ 2972 default: 2973 TRAP_ERROR(); 2974 error = EINVAL; 2975 } 2976 /* 2977 * Sometimes a generic message may be statically allocated 2978 * to avoid problems with allocating when in tight memeory situations. 2979 * Don't free it if it is so. 2980 * I break them appart here, because erros may cause a free if the item 2981 * in which case we'd be doing it twice. 2982 * they are kept together above, to simplify freeing. 2983 */ 2984 out: 2985 NG_RESPOND_MSG(error, here, item, resp); 2986 if (msg) 2987 NG_FREE_MSG(msg); 2988 return (error); 2989 } 2990 2991 /************************************************************************ 2992 Queue element get/free routines 2993 ************************************************************************/ 2994 2995 uma_zone_t ng_qzone; 2996 static int maxalloc = 4096;/* limit the damage of a leak */ 2997 static int maxdata = 512; /* limit the damage of a DoS */ 2998 static int useddata = 0; 2999 3000 TUNABLE_INT("net.graph.maxalloc", &maxalloc); 3001 SYSCTL_INT(_net_graph, OID_AUTO, maxalloc, CTLFLAG_RDTUN, &maxalloc, 3002 0, "Maximum number of queue items to allocate"); 3003 TUNABLE_INT("net.graph.maxdata", &maxdata); 3004 SYSCTL_INT(_net_graph, OID_AUTO, maxdata, CTLFLAG_RW | CTLFLAG_TUN, &maxdata, 3005 0, "Maximum number of queue data items to allocate"); 3006 3007 #ifdef NETGRAPH_DEBUG 3008 static TAILQ_HEAD(, ng_item) ng_itemlist = TAILQ_HEAD_INITIALIZER(ng_itemlist); 3009 static int allocated; /* number of items malloc'd */ 3010 #endif 3011 3012 /* 3013 * Get a queue entry. 3014 * This is usually called when a packet first enters netgraph. 3015 * By definition, this is usually from an interrupt, or from a user. 3016 * Users are not so important, but try be quick for the times that it's 3017 * an interrupt. 3018 */ 3019 static __inline item_p 3020 ng_getqblk(int flags) 3021 { 3022 item_p item = NULL; 3023 int wait; 3024 3025 wait = (flags & NG_WAITOK) ? M_WAITOK : M_NOWAIT; 3026 3027 item = uma_zalloc(ng_qzone, wait | M_ZERO); 3028 3029 #ifdef NETGRAPH_DEBUG 3030 if (item) { 3031 mtx_lock(&ngq_mtx); 3032 TAILQ_INSERT_TAIL(&ng_itemlist, item, all); 3033 allocated++; 3034 mtx_unlock(&ngq_mtx); 3035 } 3036 #endif 3037 3038 return (item); 3039 } 3040 3041 /* 3042 * Release a queue entry 3043 */ 3044 void 3045 ng_free_item(item_p item) 3046 { 3047 /* 3048 * The item may hold resources on it's own. We need to free 3049 * these before we can free the item. What they are depends upon 3050 * what kind of item it is. it is important that nodes zero 3051 * out pointers to resources that they remove from the item 3052 * or we release them again here. 3053 */ 3054 switch (item->el_flags & NGQF_TYPE) { 3055 case NGQF_DATA: 3056 atomic_subtract_int(&useddata, 1); 3057 /* If we have an mbuf still attached.. */ 3058 NG_FREE_M(_NGI_M(item)); 3059 break; 3060 case NGQF_MESG: 3061 _NGI_RETADDR(item) = 0; 3062 NG_FREE_MSG(_NGI_MSG(item)); 3063 break; 3064 case NGQF_FN: 3065 case NGQF_FN2: 3066 /* nothing to free really, */ 3067 _NGI_FN(item) = NULL; 3068 _NGI_ARG1(item) = NULL; 3069 _NGI_ARG2(item) = 0; 3070 break; 3071 } 3072 /* If we still have a node or hook referenced... */ 3073 _NGI_CLR_NODE(item); 3074 _NGI_CLR_HOOK(item); 3075 3076 #ifdef NETGRAPH_DEBUG 3077 mtx_lock(&ngq_mtx); 3078 TAILQ_REMOVE(&ng_itemlist, item, all); 3079 allocated--; 3080 mtx_unlock(&ngq_mtx); 3081 #endif 3082 uma_zfree(ng_qzone, item); 3083 } 3084 3085 /************************************************************************ 3086 Module routines 3087 ************************************************************************/ 3088 3089 /* 3090 * Handle the loading/unloading of a netgraph node type module 3091 */ 3092 int 3093 ng_mod_event(module_t mod, int event, void *data) 3094 { 3095 struct ng_type *const type = data; 3096 int s, error = 0; 3097 3098 switch (event) { 3099 case MOD_LOAD: 3100 3101 /* Register new netgraph node type */ 3102 s = splnet(); 3103 if ((error = ng_newtype(type)) != 0) { 3104 splx(s); 3105 break; 3106 } 3107 3108 /* Call type specific code */ 3109 if (type->mod_event != NULL) 3110 if ((error = (*type->mod_event)(mod, event, data))) { 3111 mtx_lock(&ng_typelist_mtx); 3112 type->refs--; /* undo it */ 3113 LIST_REMOVE(type, types); 3114 mtx_unlock(&ng_typelist_mtx); 3115 } 3116 splx(s); 3117 break; 3118 3119 case MOD_UNLOAD: 3120 s = splnet(); 3121 if (type->refs > 1) { /* make sure no nodes exist! */ 3122 error = EBUSY; 3123 } else { 3124 if (type->refs == 0) { 3125 /* failed load, nothing to undo */ 3126 splx(s); 3127 break; 3128 } 3129 if (type->mod_event != NULL) { /* check with type */ 3130 error = (*type->mod_event)(mod, event, data); 3131 if (error != 0) { /* type refuses.. */ 3132 splx(s); 3133 break; 3134 } 3135 } 3136 mtx_lock(&ng_typelist_mtx); 3137 LIST_REMOVE(type, types); 3138 mtx_unlock(&ng_typelist_mtx); 3139 } 3140 splx(s); 3141 break; 3142 3143 default: 3144 if (type->mod_event != NULL) 3145 error = (*type->mod_event)(mod, event, data); 3146 else 3147 error = EOPNOTSUPP; /* XXX ? */ 3148 break; 3149 } 3150 return (error); 3151 } 3152 3153 /* 3154 * Handle loading and unloading for this code. 3155 * The only thing we need to link into is the NETISR strucure. 3156 */ 3157 static int 3158 ngb_mod_event(module_t mod, int event, void *data) 3159 { 3160 int error = 0; 3161 3162 switch (event) { 3163 case MOD_LOAD: 3164 /* Initialize everything. */ 3165 NG_WORKLIST_LOCK_INIT(); 3166 mtx_init(&ng_typelist_mtx, "netgraph types mutex", NULL, 3167 MTX_DEF); 3168 mtx_init(&ng_idhash_mtx, "netgraph idhash mutex", NULL, 3169 MTX_DEF); 3170 mtx_init(&ng_namehash_mtx, "netgraph namehash mutex", NULL, 3171 MTX_DEF); 3172 mtx_init(&ng_topo_mtx, "netgraph topology mutex", NULL, 3173 MTX_DEF); 3174 #ifdef NETGRAPH_DEBUG 3175 mtx_init(&ng_nodelist_mtx, "netgraph nodelist mutex", NULL, 3176 MTX_DEF); 3177 mtx_init(&ngq_mtx, "netgraph item list mutex", NULL, 3178 MTX_DEF); 3179 #endif 3180 ng_qzone = uma_zcreate("NetGraph items", sizeof(struct ng_item), 3181 NULL, NULL, NULL, NULL, UMA_ALIGN_CACHE, 0); 3182 uma_zone_set_max(ng_qzone, maxalloc); 3183 netisr_register(NETISR_NETGRAPH, (netisr_t *)ngintr, NULL, 3184 NETISR_MPSAFE); 3185 break; 3186 case MOD_UNLOAD: 3187 /* You can't unload it because an interface may be using it. */ 3188 error = EBUSY; 3189 break; 3190 default: 3191 error = EOPNOTSUPP; 3192 break; 3193 } 3194 return (error); 3195 } 3196 3197 static moduledata_t netgraph_mod = { 3198 "netgraph", 3199 ngb_mod_event, 3200 (NULL) 3201 }; 3202 DECLARE_MODULE(netgraph, netgraph_mod, SI_SUB_NETGRAPH, SI_ORDER_MIDDLE); 3203 SYSCTL_NODE(_net, OID_AUTO, graph, CTLFLAG_RW, 0, "netgraph Family"); 3204 SYSCTL_INT(_net_graph, OID_AUTO, abi_version, CTLFLAG_RD, 0, NG_ABI_VERSION,""); 3205 SYSCTL_INT(_net_graph, OID_AUTO, msg_version, CTLFLAG_RD, 0, NG_VERSION, ""); 3206 3207 #ifdef NETGRAPH_DEBUG 3208 void 3209 dumphook (hook_p hook, char *file, int line) 3210 { 3211 printf("hook: name %s, %d refs, Last touched:\n", 3212 _NG_HOOK_NAME(hook), hook->hk_refs); 3213 printf(" Last active @ %s, line %d\n", 3214 hook->lastfile, hook->lastline); 3215 if (line) { 3216 printf(" problem discovered at file %s, line %d\n", file, line); 3217 } 3218 } 3219 3220 void 3221 dumpnode(node_p node, char *file, int line) 3222 { 3223 printf("node: ID [%x]: type '%s', %d hooks, flags 0x%x, %d refs, %s:\n", 3224 _NG_NODE_ID(node), node->nd_type->name, 3225 node->nd_numhooks, node->nd_flags, 3226 node->nd_refs, node->nd_name); 3227 printf(" Last active @ %s, line %d\n", 3228 node->lastfile, node->lastline); 3229 if (line) { 3230 printf(" problem discovered at file %s, line %d\n", file, line); 3231 } 3232 } 3233 3234 void 3235 dumpitem(item_p item, char *file, int line) 3236 { 3237 printf(" ACTIVE item, last used at %s, line %d", 3238 item->lastfile, item->lastline); 3239 switch(item->el_flags & NGQF_TYPE) { 3240 case NGQF_DATA: 3241 printf(" - [data]\n"); 3242 break; 3243 case NGQF_MESG: 3244 printf(" - retaddr[%d]:\n", _NGI_RETADDR(item)); 3245 break; 3246 case NGQF_FN: 3247 printf(" - fn@%p (%p, %p, %p, %d (%x))\n", 3248 _NGI_FN(item), 3249 _NGI_NODE(item), 3250 _NGI_HOOK(item), 3251 item->body.fn.fn_arg1, 3252 item->body.fn.fn_arg2, 3253 item->body.fn.fn_arg2); 3254 break; 3255 case NGQF_FN2: 3256 printf(" - fn2@%p (%p, %p, %p, %d (%x))\n", 3257 _NGI_FN2(item), 3258 _NGI_NODE(item), 3259 _NGI_HOOK(item), 3260 item->body.fn.fn_arg1, 3261 item->body.fn.fn_arg2, 3262 item->body.fn.fn_arg2); 3263 break; 3264 } 3265 if (line) { 3266 printf(" problem discovered at file %s, line %d\n", file, line); 3267 if (_NGI_NODE(item)) { 3268 printf("node %p ([%x])\n", 3269 _NGI_NODE(item), ng_node2ID(_NGI_NODE(item))); 3270 } 3271 } 3272 } 3273 3274 static void 3275 ng_dumpitems(void) 3276 { 3277 item_p item; 3278 int i = 1; 3279 TAILQ_FOREACH(item, &ng_itemlist, all) { 3280 printf("[%d] ", i++); 3281 dumpitem(item, NULL, 0); 3282 } 3283 } 3284 3285 static void 3286 ng_dumpnodes(void) 3287 { 3288 node_p node; 3289 int i = 1; 3290 mtx_lock(&ng_nodelist_mtx); 3291 SLIST_FOREACH(node, &ng_allnodes, nd_all) { 3292 printf("[%d] ", i++); 3293 dumpnode(node, NULL, 0); 3294 } 3295 mtx_unlock(&ng_nodelist_mtx); 3296 } 3297 3298 static void 3299 ng_dumphooks(void) 3300 { 3301 hook_p hook; 3302 int i = 1; 3303 mtx_lock(&ng_nodelist_mtx); 3304 SLIST_FOREACH(hook, &ng_allhooks, hk_all) { 3305 printf("[%d] ", i++); 3306 dumphook(hook, NULL, 0); 3307 } 3308 mtx_unlock(&ng_nodelist_mtx); 3309 } 3310 3311 static int 3312 sysctl_debug_ng_dump_items(SYSCTL_HANDLER_ARGS) 3313 { 3314 int error; 3315 int val; 3316 int i; 3317 3318 val = allocated; 3319 i = 1; 3320 error = sysctl_handle_int(oidp, &val, 0, req); 3321 if (error != 0 || req->newptr == NULL) 3322 return (error); 3323 if (val == 42) { 3324 ng_dumpitems(); 3325 ng_dumpnodes(); 3326 ng_dumphooks(); 3327 } 3328 return (0); 3329 } 3330 3331 SYSCTL_PROC(_debug, OID_AUTO, ng_dump_items, CTLTYPE_INT | CTLFLAG_RW, 3332 0, sizeof(int), sysctl_debug_ng_dump_items, "I", "Number of allocated items"); 3333 #endif /* NETGRAPH_DEBUG */ 3334 3335 3336 /*********************************************************************** 3337 * Worklist routines 3338 **********************************************************************/ 3339 /* NETISR thread enters here */ 3340 /* 3341 * Pick a node off the list of nodes with work, 3342 * try get an item to process off it. 3343 * If there are no more, remove the node from the list. 3344 */ 3345 static void 3346 ngintr(void) 3347 { 3348 item_p item; 3349 node_p node = NULL; 3350 3351 for (;;) { 3352 NG_WORKLIST_LOCK(); 3353 node = TAILQ_FIRST(&ng_worklist); 3354 if (!node) { 3355 NG_WORKLIST_UNLOCK(); 3356 break; 3357 } 3358 node->nd_flags &= ~NGF_WORKQ; 3359 TAILQ_REMOVE(&ng_worklist, node, nd_work); 3360 NG_WORKLIST_UNLOCK(); 3361 CTR3(KTR_NET, "%20s: node [%x] (%p) taken off worklist", 3362 __func__, node->nd_ID, node); 3363 /* 3364 * We have the node. We also take over the reference 3365 * that the list had on it. 3366 * Now process as much as you can, until it won't 3367 * let you have another item off the queue. 3368 * All this time, keep the reference 3369 * that lets us be sure that the node still exists. 3370 * Let the reference go at the last minute. 3371 * ng_dequeue will put us back on the worklist 3372 * if there is more too do. This may be of use if there 3373 * are Multiple Processors and multiple Net threads in the 3374 * future. 3375 */ 3376 for (;;) { 3377 int rw; 3378 3379 NG_QUEUE_LOCK(&node->nd_input_queue); 3380 item = ng_dequeue(&node->nd_input_queue, &rw); 3381 if (item == NULL) { 3382 NG_QUEUE_UNLOCK(&node->nd_input_queue); 3383 break; /* go look for another node */ 3384 } else { 3385 NG_QUEUE_UNLOCK(&node->nd_input_queue); 3386 NGI_GET_NODE(item, node); /* zaps stored node */ 3387 ng_apply_item(node, item, rw); 3388 NG_NODE_UNREF(node); 3389 } 3390 } 3391 NG_NODE_UNREF(node); 3392 } 3393 } 3394 3395 static void 3396 ng_worklist_remove(node_p node) 3397 { 3398 mtx_assert(&node->nd_input_queue.q_mtx, MA_OWNED); 3399 3400 NG_WORKLIST_LOCK(); 3401 if (node->nd_flags & NGF_WORKQ) { 3402 node->nd_flags &= ~NGF_WORKQ; 3403 TAILQ_REMOVE(&ng_worklist, node, nd_work); 3404 NG_WORKLIST_UNLOCK(); 3405 NG_NODE_UNREF(node); 3406 CTR3(KTR_NET, "%20s: node [%x] (%p) removed from worklist", 3407 __func__, node->nd_ID, node); 3408 } else { 3409 NG_WORKLIST_UNLOCK(); 3410 } 3411 } 3412 3413 /* 3414 * XXX 3415 * It's posible that a debugging NG_NODE_REF may need 3416 * to be outside the mutex zone 3417 */ 3418 static void 3419 ng_setisr(node_p node) 3420 { 3421 3422 mtx_assert(&node->nd_input_queue.q_mtx, MA_OWNED); 3423 3424 if ((node->nd_flags & NGF_WORKQ) == 0) { 3425 /* 3426 * If we are not already on the work queue, 3427 * then put us on. 3428 */ 3429 node->nd_flags |= NGF_WORKQ; 3430 NG_WORKLIST_LOCK(); 3431 TAILQ_INSERT_TAIL(&ng_worklist, node, nd_work); 3432 NG_WORKLIST_UNLOCK(); 3433 NG_NODE_REF(node); /* XXX fafe in mutex? */ 3434 CTR3(KTR_NET, "%20s: node [%x] (%p) put on worklist", __func__, 3435 node->nd_ID, node); 3436 } else 3437 CTR3(KTR_NET, "%20s: node [%x] (%p) already on worklist", 3438 __func__, node->nd_ID, node); 3439 schednetisr(NETISR_NETGRAPH); 3440 } 3441 3442 3443 /*********************************************************************** 3444 * Externally useable functions to set up a queue item ready for sending 3445 ***********************************************************************/ 3446 3447 #ifdef NETGRAPH_DEBUG 3448 #define ITEM_DEBUG_CHECKS \ 3449 do { \ 3450 if (NGI_NODE(item) ) { \ 3451 printf("item already has node"); \ 3452 kdb_enter(KDB_WHY_NETGRAPH, "has node"); \ 3453 NGI_CLR_NODE(item); \ 3454 } \ 3455 if (NGI_HOOK(item) ) { \ 3456 printf("item already has hook"); \ 3457 kdb_enter(KDB_WHY_NETGRAPH, "has hook"); \ 3458 NGI_CLR_HOOK(item); \ 3459 } \ 3460 } while (0) 3461 #else 3462 #define ITEM_DEBUG_CHECKS 3463 #endif 3464 3465 /* 3466 * Put mbuf into the item. 3467 * Hook and node references will be removed when the item is dequeued. 3468 * (or equivalent) 3469 * (XXX) Unsafe because no reference held by peer on remote node. 3470 * remote node might go away in this timescale. 3471 * We know the hooks can't go away because that would require getting 3472 * a writer item on both nodes and we must have at least a reader 3473 * here to be able to do this. 3474 * Note that the hook loaded is the REMOTE hook. 3475 * 3476 * This is possibly in the critical path for new data. 3477 */ 3478 item_p 3479 ng_package_data(struct mbuf *m, int flags) 3480 { 3481 item_p item; 3482 3483 if (atomic_fetchadd_int(&useddata, 1) >= maxdata) { 3484 atomic_subtract_int(&useddata, 1); 3485 NG_FREE_M(m); 3486 return (NULL); 3487 } 3488 if ((item = ng_getqblk(flags)) == NULL) { 3489 NG_FREE_M(m); 3490 return (NULL); 3491 } 3492 ITEM_DEBUG_CHECKS; 3493 item->el_flags = NGQF_DATA | NGQF_READER; 3494 NGI_M(item) = m; 3495 return (item); 3496 } 3497 3498 /* 3499 * Allocate a queue item and put items into it.. 3500 * Evaluate the address as this will be needed to queue it and 3501 * to work out what some of the fields should be. 3502 * Hook and node references will be removed when the item is dequeued. 3503 * (or equivalent) 3504 */ 3505 item_p 3506 ng_package_msg(struct ng_mesg *msg, int flags) 3507 { 3508 item_p item; 3509 3510 if ((item = ng_getqblk(flags)) == NULL) { 3511 NG_FREE_MSG(msg); 3512 return (NULL); 3513 } 3514 ITEM_DEBUG_CHECKS; 3515 /* Messages items count as writers unless explicitly exempted. */ 3516 if (msg->header.cmd & NGM_READONLY) 3517 item->el_flags = NGQF_MESG | NGQF_READER; 3518 else 3519 item->el_flags = NGQF_MESG | NGQF_WRITER; 3520 /* 3521 * Set the current lasthook into the queue item 3522 */ 3523 NGI_MSG(item) = msg; 3524 NGI_RETADDR(item) = 0; 3525 return (item); 3526 } 3527 3528 3529 3530 #define SET_RETADDR(item, here, retaddr) \ 3531 do { /* Data or fn items don't have retaddrs */ \ 3532 if ((item->el_flags & NGQF_TYPE) == NGQF_MESG) { \ 3533 if (retaddr) { \ 3534 NGI_RETADDR(item) = retaddr; \ 3535 } else { \ 3536 /* \ 3537 * The old return address should be ok. \ 3538 * If there isn't one, use the address \ 3539 * here. \ 3540 */ \ 3541 if (NGI_RETADDR(item) == 0) { \ 3542 NGI_RETADDR(item) \ 3543 = ng_node2ID(here); \ 3544 } \ 3545 } \ 3546 } \ 3547 } while (0) 3548 3549 int 3550 ng_address_hook(node_p here, item_p item, hook_p hook, ng_ID_t retaddr) 3551 { 3552 hook_p peer; 3553 node_p peernode; 3554 ITEM_DEBUG_CHECKS; 3555 /* 3556 * Quick sanity check.. 3557 * Since a hook holds a reference on it's node, once we know 3558 * that the peer is still connected (even if invalid,) we know 3559 * that the peer node is present, though maybe invalid. 3560 */ 3561 if ((hook == NULL) 3562 || NG_HOOK_NOT_VALID(hook) 3563 || (NG_HOOK_PEER(hook) == NULL) 3564 || NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook)) 3565 || NG_NODE_NOT_VALID(NG_PEER_NODE(hook))) { 3566 NG_FREE_ITEM(item); 3567 TRAP_ERROR(); 3568 return (ENETDOWN); 3569 } 3570 3571 /* 3572 * Transfer our interest to the other (peer) end. 3573 */ 3574 peer = NG_HOOK_PEER(hook); 3575 NG_HOOK_REF(peer); 3576 NGI_SET_HOOK(item, peer); 3577 peernode = NG_PEER_NODE(hook); 3578 NG_NODE_REF(peernode); 3579 NGI_SET_NODE(item, peernode); 3580 SET_RETADDR(item, here, retaddr); 3581 return (0); 3582 } 3583 3584 int 3585 ng_address_path(node_p here, item_p item, char *address, ng_ID_t retaddr) 3586 { 3587 node_p dest = NULL; 3588 hook_p hook = NULL; 3589 int error; 3590 3591 ITEM_DEBUG_CHECKS; 3592 /* 3593 * Note that ng_path2noderef increments the reference count 3594 * on the node for us if it finds one. So we don't have to. 3595 */ 3596 error = ng_path2noderef(here, address, &dest, &hook); 3597 if (error) { 3598 NG_FREE_ITEM(item); 3599 return (error); 3600 } 3601 NGI_SET_NODE(item, dest); 3602 if ( hook) { 3603 NG_HOOK_REF(hook); /* don't let it go while on the queue */ 3604 NGI_SET_HOOK(item, hook); 3605 } 3606 SET_RETADDR(item, here, retaddr); 3607 return (0); 3608 } 3609 3610 int 3611 ng_address_ID(node_p here, item_p item, ng_ID_t ID, ng_ID_t retaddr) 3612 { 3613 node_p dest; 3614 3615 ITEM_DEBUG_CHECKS; 3616 /* 3617 * Find the target node. 3618 */ 3619 dest = ng_ID2noderef(ID); /* GETS REFERENCE! */ 3620 if (dest == NULL) { 3621 NG_FREE_ITEM(item); 3622 TRAP_ERROR(); 3623 return(EINVAL); 3624 } 3625 /* Fill out the contents */ 3626 NGI_SET_NODE(item, dest); 3627 NGI_CLR_HOOK(item); 3628 SET_RETADDR(item, here, retaddr); 3629 return (0); 3630 } 3631 3632 /* 3633 * special case to send a message to self (e.g. destroy node) 3634 * Possibly indicate an arrival hook too. 3635 * Useful for removing that hook :-) 3636 */ 3637 item_p 3638 ng_package_msg_self(node_p here, hook_p hook, struct ng_mesg *msg) 3639 { 3640 item_p item; 3641 3642 /* 3643 * Find the target node. 3644 * If there is a HOOK argument, then use that in preference 3645 * to the address. 3646 */ 3647 if ((item = ng_getqblk(NG_NOFLAGS)) == NULL) { 3648 NG_FREE_MSG(msg); 3649 return (NULL); 3650 } 3651 3652 /* Fill out the contents */ 3653 item->el_flags = NGQF_MESG | NGQF_WRITER; 3654 NG_NODE_REF(here); 3655 NGI_SET_NODE(item, here); 3656 if (hook) { 3657 NG_HOOK_REF(hook); 3658 NGI_SET_HOOK(item, hook); 3659 } 3660 NGI_MSG(item) = msg; 3661 NGI_RETADDR(item) = ng_node2ID(here); 3662 return (item); 3663 } 3664 3665 /* 3666 * Send ng_item_fn function call to the specified node. 3667 */ 3668 3669 int 3670 ng_send_fn(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2) 3671 { 3672 3673 return ng_send_fn1(node, hook, fn, arg1, arg2, NG_NOFLAGS); 3674 } 3675 3676 int 3677 ng_send_fn1(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2, 3678 int flags) 3679 { 3680 item_p item; 3681 3682 if ((item = ng_getqblk(flags)) == NULL) { 3683 return (ENOMEM); 3684 } 3685 item->el_flags = NGQF_FN | NGQF_WRITER; 3686 NG_NODE_REF(node); /* and one for the item */ 3687 NGI_SET_NODE(item, node); 3688 if (hook) { 3689 NG_HOOK_REF(hook); 3690 NGI_SET_HOOK(item, hook); 3691 } 3692 NGI_FN(item) = fn; 3693 NGI_ARG1(item) = arg1; 3694 NGI_ARG2(item) = arg2; 3695 return(ng_snd_item(item, flags)); 3696 } 3697 3698 /* 3699 * Send ng_item_fn2 function call to the specified node. 3700 * 3701 * If an optional pitem parameter is supplied, its apply 3702 * callback will be copied to the new item. If also NG_REUSE_ITEM 3703 * flag is set, no new item will be allocated, but pitem will 3704 * be used. 3705 */ 3706 int 3707 ng_send_fn2(node_p node, hook_p hook, item_p pitem, ng_item_fn2 *fn, void *arg1, 3708 int arg2, int flags) 3709 { 3710 item_p item; 3711 3712 KASSERT((pitem != NULL || (flags & NG_REUSE_ITEM) == 0), 3713 ("%s: NG_REUSE_ITEM but no pitem", __func__)); 3714 3715 /* 3716 * Allocate a new item if no supplied or 3717 * if we can't use supplied one. 3718 */ 3719 if (pitem == NULL || (flags & NG_REUSE_ITEM) == 0) { 3720 if ((item = ng_getqblk(flags)) == NULL) 3721 return (ENOMEM); 3722 } else { 3723 if ((pitem->el_flags & NGQF_TYPE) == NGQF_DATA) 3724 atomic_subtract_int(&useddata, 1); 3725 item = pitem; 3726 } 3727 3728 item->el_flags = NGQF_FN2 | NGQF_WRITER; 3729 NG_NODE_REF(node); /* and one for the item */ 3730 NGI_SET_NODE(item, node); 3731 if (hook) { 3732 NG_HOOK_REF(hook); 3733 NGI_SET_HOOK(item, hook); 3734 } 3735 NGI_FN2(item) = fn; 3736 NGI_ARG1(item) = arg1; 3737 NGI_ARG2(item) = arg2; 3738 if (pitem != NULL && (flags & NG_REUSE_ITEM) == 0) 3739 item->apply = pitem->apply; 3740 return(ng_snd_item(item, flags)); 3741 } 3742 3743 /* 3744 * Official timeout routines for Netgraph nodes. 3745 */ 3746 static void 3747 ng_callout_trampoline(void *arg) 3748 { 3749 item_p item = arg; 3750 3751 ng_snd_item(item, 0); 3752 } 3753 3754 3755 int 3756 ng_callout(struct callout *c, node_p node, hook_p hook, int ticks, 3757 ng_item_fn *fn, void * arg1, int arg2) 3758 { 3759 item_p item, oitem; 3760 3761 if ((item = ng_getqblk(NG_NOFLAGS)) == NULL) 3762 return (ENOMEM); 3763 3764 item->el_flags = NGQF_FN | NGQF_WRITER; 3765 NG_NODE_REF(node); /* and one for the item */ 3766 NGI_SET_NODE(item, node); 3767 if (hook) { 3768 NG_HOOK_REF(hook); 3769 NGI_SET_HOOK(item, hook); 3770 } 3771 NGI_FN(item) = fn; 3772 NGI_ARG1(item) = arg1; 3773 NGI_ARG2(item) = arg2; 3774 oitem = c->c_arg; 3775 if (callout_reset(c, ticks, &ng_callout_trampoline, item) == 1 && 3776 oitem != NULL) 3777 NG_FREE_ITEM(oitem); 3778 return (0); 3779 } 3780 3781 /* A special modified version of untimeout() */ 3782 int 3783 ng_uncallout(struct callout *c, node_p node) 3784 { 3785 item_p item; 3786 int rval; 3787 3788 KASSERT(c != NULL, ("ng_uncallout: NULL callout")); 3789 KASSERT(node != NULL, ("ng_uncallout: NULL node")); 3790 3791 rval = callout_stop(c); 3792 item = c->c_arg; 3793 /* Do an extra check */ 3794 if ((rval > 0) && (c->c_func == &ng_callout_trampoline) && 3795 (NGI_NODE(item) == node)) { 3796 /* 3797 * We successfully removed it from the queue before it ran 3798 * So now we need to unreference everything that was 3799 * given extra references. (NG_FREE_ITEM does this). 3800 */ 3801 NG_FREE_ITEM(item); 3802 } 3803 c->c_arg = NULL; 3804 3805 return (rval); 3806 } 3807 3808 /* 3809 * Set the address, if none given, give the node here. 3810 */ 3811 void 3812 ng_replace_retaddr(node_p here, item_p item, ng_ID_t retaddr) 3813 { 3814 if (retaddr) { 3815 NGI_RETADDR(item) = retaddr; 3816 } else { 3817 /* 3818 * The old return address should be ok. 3819 * If there isn't one, use the address here. 3820 */ 3821 NGI_RETADDR(item) = ng_node2ID(here); 3822 } 3823 } 3824 3825 #define TESTING 3826 #ifdef TESTING 3827 /* just test all the macros */ 3828 void 3829 ng_macro_test(item_p item); 3830 void 3831 ng_macro_test(item_p item) 3832 { 3833 node_p node = NULL; 3834 hook_p hook = NULL; 3835 struct mbuf *m; 3836 struct ng_mesg *msg; 3837 ng_ID_t retaddr; 3838 int error; 3839 3840 NGI_GET_M(item, m); 3841 NGI_GET_MSG(item, msg); 3842 retaddr = NGI_RETADDR(item); 3843 NG_SEND_DATA(error, hook, m, NULL); 3844 NG_SEND_DATA_ONLY(error, hook, m); 3845 NG_FWD_NEW_DATA(error, item, hook, m); 3846 NG_FWD_ITEM_HOOK(error, item, hook); 3847 NG_SEND_MSG_HOOK(error, node, msg, hook, retaddr); 3848 NG_SEND_MSG_ID(error, node, msg, retaddr, retaddr); 3849 NG_SEND_MSG_PATH(error, node, msg, ".:", retaddr); 3850 NG_FWD_MSG_HOOK(error, node, item, hook, retaddr); 3851 } 3852 #endif /* TESTING */ 3853 3854